feat(android): the phone's "More" is a bottom sheet

The tab bar's fifth item opened `<app-sidebar>` in a `wa-drawer`
sliding in from the side, which is a desktop shape put on a phone: a
200px column of a 424px screen, opening away from the thumb that asked
for it, with the rest of its 400px band empty. It also had three nested
scrollers in it -- the dialog, its body, and the sidebar's own
`overflow-y: auto` host -- so which box a drag moved depended on where
the finger landed, which is the "only part of the screen scrolls under
my finger" in the report.

It is the same element with `placement="bottom"` and `without-header`,
so the surface is the sheet #60 already built rather than a second
pattern: a `wa-drawer` is a native `<dialog>` opened with `showModal()`,
which is exactly the top layer that finding rests on, so the focus
trap, Escape, tap-outside and `wa-after-hide` come along unchanged and
nothing new has to be proved about paint containment.

The sidebar is still mounted rather than re-listed as data, because the
shell's own copy is `display: none` below 600px rather than removed --
a second list drawing `nav-*` handles is the duplicate-testid failure
this component already renders conditionally to avoid. What `expanded`
means had to grow to say the host owns the *box*: `app-sidebar` writes
an inline width and caps itself at 400px, which beats any rule the host
could write, so the width, the scrolling and the mouse-only resize
handle now follow that attribute. The rows are 48px below 600px, stated
in the sidebar's own stylesheet since that is the only place it renders
there.

Measured in the running app at 424x439: the sheet is 424 wide, 373 tall
(85vh, so there is an outside to tap), rows 48px, one scroller with
`overscroll-behavior: contain`, and Settings' row reachable at the end
of it. Desktop and Compact are untouched.

Closes #71

.gitignore

@@ -88,3 +88,8 @@ build/android/overlay.json
 # Written by @semantic-release/changelog purely to carry the release notes
 # into scripts/gitea-release.sh; the release page is the changelog.
 .release-notes.md
+
+# Agent session log: local scratch, not repo memory (that is CLAUDE.md
+# and .planning/). Written by the scheduled backlog runs.
+.pi/journal.md
+.pi/schedule-prompts.json

.pi/prompts/next-issue.md

@@ -0,0 +1,142 @@
+---
+description: Take on the next actionable backlog issue end to end, and stop
+---
+Take on exactly one issue from the YellowJacket backlog, end to end, and stop.
+
+Repo: yonlu/yellowjacket at https://git.ljones.me — API base
+https://git.ljones.me/api/v1/repos/yonlu/yellowjacket, auth with
+`-H "Authorization: token $GITEA_TOKEN"`. Default branch is `main`.
+
+## 1. Orient before you pick
+
+Read, in this order: `CLAUDE.md` (the architecture and the reasons behind
+it), `.pi/journal.md` (what happened last), `.planning/NOTES.md` (what was
+already considered and rejected), and `.planning/plans/active/`. Do not skip
+this because the issue looks small — most of this codebase's traps are
+written down in exactly one of those four places, and the ones that bite are
+the ones you didn't read.
+
+## 2. Pick the issue
+
+List open issues. Choose the single highest-value one that is *actionable
+right now*:
+
+- Order by `Priority/Critical` → `High` → `Medium` → `Low`. Within a tier,
+  prefer `Reviewed/Confirmed`, then `Kind/Bug` over `Kind/Enhancement` over
+  `Kind/Feature`.
+- Consult issue #73 (the roadmap) — if it sequences the candidates, that
+  ordering wins over the label ordering.
+- **Skip** anything labelled `Status/Blocked`, `Status/In Progress`,
+  `Status/Abandoned`, `Reviewed/Won't Fix`, `Reviewed/Duplicate`,
+  `Reviewed/Invalid`, or already carrying an open PR.
+- **Skip anything someone else is already on.** The label is not the only
+  claim, because a concurrent session may not have applied it — several pi
+  sessions run against this repo from separate worktrees under
+  `~/.paseo/worktrees/`. Run `git ls-remote --heads origin` and skip any
+  issue whose number or slug matches an existing branch (`60-…`,
+  `fix/<slug>`). A duplicated fix costs more than a skipped issue.
+- **Skip** anything that cannot be verified without hardware you do not
+  have: physical-device Android behaviour (audio output, on-device file
+  writes, real gesture input). A browser at 424px is not a phone — see the
+  Chrome 113 section of `CLAUDE.md`.
+- **Skip** intermittent-failure issues unless you can reproduce the failure
+  on demand within a few minutes. Chasing a 1-in-3 flake is an unbounded
+  task and does not belong in a scheduled run.
+- If nothing qualifies, say so, do nothing, and stop. An empty run is a
+  correct outcome.
+
+## 3. Claim it
+
+Add `Status/In Progress` to the issue and comment that you are picking it
+up. Then branch:
+
+```
+git fetch origin && git checkout -b <type>/<short-slug> origin/main
+```
+
+`<type>` matches the issue's `Kind` (`fix/`, `feat/`, `refactor/`, `test/`,
+`docs/`, `ci/`). Branch from `origin/main`, never by checking out `main`
+itself — this repo is worked from several git worktrees at once and `main`
+is checked out in one of them, so `git checkout main` fails outright.
+
+## 4. Do the work
+
+Fix the issue that was reported and nothing else. Match the surrounding
+code's style. Follow the constraints in `CLAUDE.md` rather than reasoning
+from first principles — where it explains why something is shaped the way it
+is, that shape is load-bearing and there is usually a test pinning it.
+
+**Anything else you discover becomes a new issue, not a bigger diff.** File
+it with the right `Area/`, `Kind/`, `Priority/` labels, describe the
+symptom before the theory, and link it from your PR. Scope creep is the
+failure mode this instruction exists to prevent.
+
+If the work turns out to be materially larger than the issue implied, stop:
+comment on the issue with what you found and what it would actually take,
+remove `Status/In Progress`, push nothing, and end the run.
+
+## 5. Verify — the right tier, not the cheapest one
+
+Run `make generate` if you touched `.sql` or `.templ`, and `make bindings`
+if you changed a bound Go signature. Then run what the change actually
+demands:
+
+- Go change → `make lint` and `make test` (both cover all three build
+  configurations).
+- Frontend component or store → `make ui-test`.
+- User-visible flow → `make e2e` against `make dev-headless`. **Check the
+  port first**: `ss -ltn | grep 34115`. If it is occupied, another worktree
+  is already running the app — do not start a second one and do not run
+  `make e2e`. Attaching to someone else's build produces a green result
+  about code that is not yours, which is worse than no result. Either
+  choose an issue that does not need this tier, or stop and say why.
+- Anything cosmetic or layout-related → look at a screenshot. Several bugs
+  in this repo's history were invisible to every assertion and obvious in an
+  image.
+
+A tier you skipped is a claim you did not check. If a tier fails for reasons
+unrelated to your change, say so explicitly rather than quietly moving on.
+
+## 6. Keep the documentation true
+
+If you changed structure, behaviour, or a constraint, update `CLAUDE.md` in
+the same commit. That file is this project's memory; a change that leaves it
+describing the old shape is worse than no change. Append a short entry to
+`.pi/journal.md` covering what you did, what you verified, and what you left
+open.
+
+## 7. Commit and open the PR
+
+Conventional Commits, imperative subject, ≤72 chars, scope optional. The
+body explains *why*. Push the branch — never push to `main`, never
+force-push.
+
+Open the PR:
+
+```
+curl -sS -X POST \
+  -H "Authorization: token $GITEA_TOKEN" \
+  -H "Content-Type: application/json" \
+  https://git.ljones.me/api/v1/repos/yonlu/yellowjacket/pulls \
+  -d '{"head":"<branch>","base":"main","title":"<subject>","body":"<body>"}'
+```
+
+The body states: what the issue was, what you changed and why, **which
+verification tiers you ran and their results**, anything you deliberately
+did not do, and `Closes #<n>`.
+
+Then wait for CI (`ci.yml`, jobs `check` and `e2e`) and report the result on
+the PR. If it fails, read the log — `gitea_ci`'s `job_logs` 404s on this
+Gitea build, so use
+`GET /api/v1/repos/yonlu/yellowjacket/actions/runs/<run>/jobs` for per-step
+status and `GET /api/v1/repos/yonlu/yellowjacket/actions/jobs/<id>/logs` for
+the log — and fix it. Two consecutive failed CI runs on the same cause: stop,
+comment what you know on the PR, and leave it for a human.
+
+**Do not merge.** Comment on the issue linking the PR, leave
+`Status/In Progress` on, and end the run.
+
+## Finally
+
+Report in three lines: which issue you took, what state it is in
+(PR open / CI green / stopped and why), and any issues you filed.

.pi/skills/yellowjacket-dev/SKILL.md

@@ -130,7 +130,13 @@ reference, because you need them *before* the failure, not after.
   what you otherwise get is `Property 'scroll' does not exist on type
   'CSSResult'` pointing at a line of prose, or every test in the suite
   failing to import. It went in after the trap cost a fourth session in
-  which its own warning had been read twice.
+  which its own warning had been read twice. **The same command carries
+  a second CSS check**: a nested rule whose selector starts with an
+  element name (`audio-player { … }` rather than `& audio-player { … }`)
+  is silently dropped by the device's Chrome 113 and by nothing else, so
+  every tier you can run renders it correctly. Run it after touching
+  `index.css` or any `css` literal; a rule directly inside a top-level
+  `@media` is not nested and is not flagged.
 - **A failing CI job's log is reachable even when `gitea_ci job_logs`
   says it is not.** That endpoint 404s on this Gitea build. The REST
   API answers, with the `GITEA_TOKEN` already in the environment:
@@ -152,7 +158,7 @@ only climb when it cannot.
 | You changed | Run | Cost |
 |---|---|---|
 | A Lit component, a store, the shortcut service | `make ui-test` | ~2 s, no app |
-| …and it renders differently | `make ui-visual` | + 6 baselines, opt-in |
+| …and it renders differently | `make ui-visual` | + 10 baselines, opt-in, never gates |
 | Any Go code | `make test` | 3 passes, ~2 min |
 | A service that emits events | `make test` — assert on the payload, see `backend/queue/emit_test.go` | in-process, no app |
 | A bound method or a bound struct field | `make bindings` then `make ui-test` | ~1.5 s + 2 s |
@@ -174,6 +180,13 @@ less than it looks.)
 
 Two rules about climbing:
 
+- **If you moved a component's geometry, run `make ui-visual` and
+  refresh that component's baseline in the same commit.** Nothing else
+  will: it is the one tier in this repo no hook and no CI job runs, and
+  it cannot be one — its references are machine-specific, measured in
+  [references/ui-tier.md](references/ui-tier.md). Four of them drifted
+  across three merges before anyone noticed (#196). Read the image;
+  never bless a reference you did not cause.
 - **A component test passing is not the app rendering.** If you touched
   anything in `frontend/src`, verify it in the real app too — start it
   headless, `screenshot --filename=/tmp/shot.png`, and *read the PNG*.

.pi/skills/yellowjacket-dev/references/android-tier.md

@@ -8,13 +8,29 @@ This tier answers "does the phone build run", nothing else. It is not a
 spec tier, it does not run in CI, and the app is not a usable Android
 player yet (plan 015 says why, at length).
 
-## Three facts that make failure invisible
+## Two facts that make failure invisible
 
-**Go's stdout does not reach logcat.** An Android app's fd 1 and 2 go to
+There were three. The first was that **Go's stdout does not reach
-`/dev/null`. Every `slog` line the app writes is discarded — including
+logcat** — an Android app's fd 1 and 2 go to `/dev/null`, so every
-the one naming the error it is about to exit on. `setprop
+`slog` line the app wrote was discarded, including the one naming the
-log.redirect-stdio true` does not help: it redirects the *Java*
+error it was about to exit on. That is fixed (#160):
-runtime's `System.out`, and the Go code is a c-shared native library.
+`backend/androidlog` is a `slog.Handler` over `__android_log_write`,
+selected in `main()` by build tag, and the app's whole diagnostic
+stream now arrives under the `yellowjacket` tag, which `make
+android-logs` filters for.
+
+What remains true about it is the part that misleads: **`setprop
+log.redirect-stdio true` still does not help**, because it redirects
+the *Java* runtime's `System.out` and the Go code is a c-shared native
+library. Nothing that reaches logcat here does so through stdout, so
+anything printed with `fmt.Println` is still lost. Log with `slog`.
+
+The tag is a fixed string rather than the application id, and that is
+load-bearing rather than tidy: the debug build carries
+`applicationIdSuffix ".dev"` so it can be installed beside the release
+app, and it is the only build whose WebView can be inspected — so a tag
+derived from the id would be filtered out on the one build anybody
+debugging this app is running.
 
 **`os.Exit` is a silent death.** `main()` ends several failure paths in
 `os.Exit(1)`. From Android's side that is a process that vanished:
@@ -34,7 +50,10 @@ the wrong question. `make android-smoke` asks the right one — is it the
 The tell, once you know it: `I/WailsBridge: Wails bridge initialized`
 followed immediately by a new pid doing the same thing. That means the
 native library loaded, the JNI bridge came up, Go's `main()` ran, and
-`main()` left. Work backwards through its `os.Exit(1)` paths.
+`main()` left. Work backwards through its `os.Exit(1)` paths — and
+since #160, **read the `E/yellowjacket` line above it first**, because
+every one of those paths logs the error before it exits. That line is
+what #52 spent months without.
 
 ## What to run
 
@@ -524,6 +543,61 @@ Four things about it, each of which costs an hour if met cold:
   app.yellowjacket.dev android.permission.READ_MEDIA_AUDIO` (and
   `POST_NOTIFICATIONS`) ahead of the launch skips it.
 
+### Getting the app into a state worth measuring
+
+A fresh install is **not** a neutral starting point, and three things
+about it will each cost you a measurement.
+
+**It downloads the real catalog.** `YJ_CORE_INDEX_URL` is stubbed in
+`dev-headless.sh` and in CI and is *real* here, so the app spends its
+first minutes fetching ~0.6 GB and `job-band` is **103px of a 439px
+screen** while it does. Every vertical number taken in that state is
+wrong -- one #51 measurement had the album art at 0px and it was
+entirely this.
+
+`__yj.call("explore.Service.StopIndexBuild", [])` stops it and returns
+cleanly. **It then starts again within seconds.** So stop it
+*immediately before* the measurement rather than once at the beginning,
+and check `jobs.Service.GetJobs` afterwards -- an empty array is the
+only proof. `jobs.Service.ClearFinishedJobs` tidies the finished rows
+that otherwise keep the band open.
+
+**A library added over the bridge does not dismiss the first-run
+wizard.** `library.Library.AddLibrary` works and scans, but the wizard
+checks for an existing library once, on mount, and its "Get Started"
+button gates on a directory chosen *in the wizard* -- so it stays up
+with a correctly disabled button over everything you are trying to
+measure. Nothing is broken; reload the page and it is gone. This reads
+exactly like a tap being swallowed, which is the expensive part.
+
+**Scoped storage decides where the music can be.** `/sdcard/Music/...`
+plus `pm grant <pkg> android.permission.READ_MEDIA_AUDIO` works and
+`AddLibrary` takes the plain path; a push into
+`/sdcard/Android/data/<pkg>/files/` looks like it worked and then is not
+there. Some builds additionally want
+`appops set <pkg> MANAGE_EXTERNAL_STORAGE allow`, and until they have it
+the app opens the *system* "All files access" screen on launch -- so
+`dumpsys window | grep mCurrentFocus` naming `com.android.settings` is
+that, not a crash.
+
+### A note on quoting `make android-eval`
+
+`EXPR='...'` is a single-quoted shell word, so anything with a quote or
+an apostrophe in it -- a file path like `Blazo, 49'ers - ...`, or a
+snippet containing a string literal -- breaks in a way that reads as a
+JavaScript error. Put the expression in a file and pass it positionally:
+
+```bash
+node ./scripts/android-eval.mjs "$(cat /tmp/probe.js)"
+```
+
+That is the same script `make android-eval` wraps, so nothing is lost.
+Two things worth knowing about it: it does **not** await a promise, so
+an async call has to park its result (`window.__r = ...`) and be read
+back in a second eval; and the shim from the section below is lost on
+every reload and every app restart, along with the devtools socket,
+whose name carries the pid.
+
 ### Calling a binding on the device
 
 **The runtime call does not go over HTTP on Android**, and this is worth

.pi/skills/yellowjacket-dev/references/ui-tier.md

@@ -78,9 +78,58 @@ synchronously.
   Microtasks and not a timer, deliberately: a timer hangs forever under
   the suites that install fake ones.
 
-Visual baselines are font-hinting and compositing sensitive, which is
+## The visual tier does not gate, and that is measured (#196)
-why they are opt-in: they only mean anything on the machine that
+
-recorded them.
+`make ui-visual` is the same suite with nine `toMatchScreenshot`
+baselines switched on. **Nothing runs it but a person**, deliberately,
+and the reason is a number rather than a preference: the committed
+baselines were recorded on Arch, and replayed in a bare `ubuntu:24.04`
+container — CI's `check` image — three of them fail for reasons that
+have nothing to do with any component.
+
+| baseline | Arch | ubuntu:24.04 |
+|---|---|---|
+| `page-header` filtered-by-search | passes | ratio 0.03 differ, against a 0.02 allowance |
+| `track-info` | passes | ratio 0.03 differ |
+| `seek-bar` | 1152×18 | 1152×17 |
+
+The two references that were genuinely stale did not even agree about
+their *new* size — `now-playing` renders 1152×65 on Arch and 1152×64 in
+the container. So moving CI's `check` job from `make ui-test` to
+`make ui-visual` is not a one-line change: it needs a second,
+container-recorded baseline set, which every local run would then fail
+against. That is the same trap the other way round, and a pre-push hook
+is the same fault again — one machine's baselines against everybody
+else's renderer.
+
+So the tier stays local and opt-in, and the rule that replaces the gate
+is:
+
+- **A change that moves a component's geometry refreshes that
+  component's reference in the same commit, having read the image.**
+  Look at the PNG; the dimensions in the failure message are the cheap
+  half of the answer.
+- **Never refresh a reference you did not cause.** #196 exists because
+  four of them drifted across three unrelated merges, and every red run
+  made the next person likelier to stop running the tier than to read
+  it.
+- **State the world the shot is taken in.** The stores are singletons,
+  so a visual case that sets nothing photographs whatever the previous
+  case left behind — which is how the sidebar's baseline came to have
+  Tracks lit and `now-playing`'s to be playing from a dynamic mix.
+- **Record one file with `make ui-visual-update UI_ARGS=<path>`**, and
+  check `git status` before committing either way. That filter is only
+  honoured since #204: the recipe was a bare `--update`, and vitest
+  takes the following positional as the flag's value, so the path was
+  swallowed and *every* baseline was re-recorded — blessing any stale
+  one in silence.
+
+What the tier is worth, for the record: it is a *layout* check, blind to
+colour (the component tier has no `:root`, so it renders the fallbacks —
+`make ui-visual` passed unchanged through a whole palette rewrite,
+twice), and it has caught one thing nothing else could — swapping
+`library-status-indicator`'s `<button>` for a `<span>` lost the UA
+stylesheet's `box-sizing` and grew the badge 36→38px.
 
 ## Bindings
 

.planning/NOTES.md

@@ -4487,3 +4487,545 @@ is not orphaned" and "a docked column is not in the stack" are both
 vacuously true of a build that pushes no entry at all. Reverting the
 source and re-running is what established which were which, and the
 file says so in its header rather than implying all nine reproduce.
+
+## The phone's transport, and three things that only a screenshot or a stash could see (measured 2026-08-21)
+
+#59 and #56 were done as one PR — argued on #73 first — because they are
+the same row of pixels: one removes controls from the phone's bar and
+the other enlarges what is left, and both are one property on
+`player-controls`. Measured at 424x439 before:
+
+| control | before | after |
+|---|---|---|
+| bar: shuffle / prev / play / next / repeat | 33x21 each | prev/next 44, play 56, shuffle+repeat moved |
+| bar: favourite | **18x14** | 44x44 |
+| bar: queue button | 33x29 | gone (#59) |
+| Now Playing: all five | 33x21 each | 44, play 64 |
+| desktop bar: all five | 33x21 | **33x21** |
+
+Four things cost a cycle each and are worth keeping.
+
+**A `<button>` does not inherit its font from its parent.** The UA
+stylesheet gives it one, so `font-size: inherit` on a button is a
+*change*, not a no-op: it took every desktop control from 33x21 to
+36x24 by moving them from 13.3px to the shell's 16px. Nothing failed.
+The only way it surfaced was measuring the baseline by stashing the file
+and re-running.
+
+**And the pixel it was first pinned with was the wrong assertion.** The
+spec asserted the literal `'33x21'`, measured in Chromium — and WebKit
+draws the same button **36x24**, so it failed in CI on a build where
+nothing was wrong. A button's box comes from the UA stylesheet when the
+author sets nothing, and what each UA sets is its own business. What
+must not happen is that *we* set something, so that is what it asserts
+now: `min-width` and `min-height` compute to `0px`, and the font-size
+still equals that of a bare `<button>` probed in the same page. That
+form catches the `font-size: inherit` regression in either engine —
+checked by re-introducing it — and it is the same "assert the
+mechanism" move `queue-as-a-screen.spec.ts` makes about containment.
+
+It is also the second time in two sessions that **CI's WebKit was the
+only tier that could see something**, which is the argument for checking
+that step ran rather than trusting the run's conclusion.
+
+**A rule at the bottom of `index.css` still loses to a nested rule
+above it.** The phone block is last on purpose because a media query
+adds no specificity — but `#queue-button` is written *nested* inside
+`.bottom-bar`, so it builds to a descendant selector one class more
+specific, and a bare `#queue-button { display: none }` in the phone
+block did nothing at all. Silently: the button simply stayed. Nesting
+adds specificity the source does not show.
+
+**Removing a control moved the question of how you reach what is left,
+and ten specs were quietly asserting the old answer.** Hiding the bar's
+queue button failed ten tests in four files about the back stack and
+about layout, every one of which opened the queue by clicking
+`#queue-button`. `openTheQueue` in `e2e/support/fixtures.ts` is the
+route *this viewport* offers, and the fix was to stop hard-coding one.
+
+**And the route it takes did not exist in the state that matters.**
+`now-playing` renders two branches, and the no-track one had no
+`.expand` button — so with nothing loaded there was no way to Now
+Playing, and once the queue button left the bar the queue was
+unreachable outright. The queue is persisted across restarts, so this
+is a state the app launches into, not a corner. It first appeared as a
+*flake* (#168: the long-lived e2e app meant whether a track was loaded
+depended on which spec ran first), which is worth remembering — a leak
+made a deterministic bug look like a race.
+
+## Now Playing does not fit a 439px screen, and #56 makes that visible (measured 2026-08-21)
+
+Two separate things, and only the first is a defect.
+
+**The art overflowed its own box and drew over the header and the
+title.** It is `width: min(100%, 60vh); aspect-ratio: 1`, so its height
+is derived from its width and bounded by nothing — 60vh bounds the
+*viewport*, not the room left over, and those differ by all the chrome
+above and below. `max-height: 100%` is the fix and shipped with #56.
+Pre-existing: screenshotted on `main`. **Found by reading a screenshot,
+which is the only tier that can see it** — nothing fails, the shell does
+not overflow, and every control is still hittable.
+
+**With that fixed, the art is a 39px sliver**, because the transport is
+now 172px of a 439px screen. That is a consequence of #56 rather than a
+fault in it, and it is filed as #172 with the per-element budget. #64
+(no in-app volume on Android) is ~30px of pure gain there and #51 is the
+umbrella; folding shuffle and repeat back onto the primary row was
+considered and rejected — it buys 52px, leaves the art at 91px, and
+costs a third arrangement of the same five buttons.
+
+## The volume is not ours on Android, and the predicate could not be a width (measured 2026-08-21)
+
+#64 asked for the in-app volume control to be absent on Android. Its
+first Finding said `volume-control` "already stands down at narrow
+widths", which was true of one of its two copies and is why the issue
+had been read as nearly done. The bar's copy goes by width; the
+full-screen view's copy was deliberately kept, with a comment saying a
+slider does belong there.
+
+**The crux was platform versus width, and three options were on the
+issue.** What settled it is that the *backend* half of the same issue —
+pin the level at 1.0 — makes a width rule wrong on the platform the
+issue is about: an Android tablet at >=600px gets the bottom bar, and
+the bar's slider would then move a level that is pinned. That is a
+control that cannot act, which `library-status-indicator` already
+settled is worse than none. The same rule is wrong the other way below
+600px, where a narrow desktop window has no hardware keys.
+
+So the frontend asks the player — `SystemOwnsVolume` — and the answer
+is right at every width in both mount points. **The predicate is named
+after the capability rather than the platform**, which is what makes it
+testable: only `platformOwnsVolume` is behind a build tag, in two files
+that declare nothing else, and everything else is decided against a
+field a Go test sets either way. `frontend/test/components/
+volume-ownership.test.ts` stubs the binding and so exercises the
+*Android* rendering on an ordinary Linux runner; both of its tests were
+confirmed to fail on the build before the change.
+
+**Measured at 424x439, by flipping `platformOwnsVolume` to true in the
+`!android` file and rebuilding** — the real binding, the real store, the
+real component, everything except the tag:
+
+| element | before | after |
+|---|---|---|
+| header | 48 | 48 |
+| **album art** | **39** | **68** |
+| title / artist / album | 63 | 63 |
+| transport (seek + controls + volume) | **172** | **143** |
+| — seek bar | 19 | 19 |
+| — player-controls | 116 | 116 |
+| — volume-control | 21 | **0** |
+
+29px, which is the 21px control plus the 8px flex gap it stops drawing:
+a gap is only painted between boxes, so `:host([hidden])` costs the
+transport nothing rather than leaving a hole. That is #172's "~30px of
+pure gain" confirmed, and the art is 74% larger. It is still the
+second-smallest thing on the screen, which is #51's evidence.
+
+Three smaller things worth keeping.
+
+**`:host([hidden])` has to be written down.** The UA's `[hidden]`
+rule is `display: none`, but `volume-control`'s own `:host` sets
+`display: inline-flex` and outranks it — so setting `hidden` alone
+hides nothing. Same family as the nested-`#queue-button` specificity
+trap from the session before.
+
+**Rendering `nothing` and hiding the host are two different
+assertions**, and the component test makes both: an empty shadow root
+is what stops a by-role or positional query finding a button that
+cannot act, and `hidden` is what stops the host occupying space. Either
+alone passes on a build that gets the other wrong.
+
+**The bar's centring survives the control going away.** #23's outer
+columns are the same `min()` expression rather than content-sized, so
+at 900px with the volume gone the bar's centre, `audio-player`'s centre
+and `player-controls`' centre are all 450 — checked, because "the
+transport is centred with a slider bolted to one side" is the fault
+that rule exists for and removing the slider is the obvious way to
+re-break it.
+
+**What no tier here can check**: the constant itself, and ducking
+against a real audio-focus change. The first is a source sweep
+(`TestPlatformVolumeOwnershipIsDeclaredOncePerPlatform`), the second is
+`TestSystemVolumeStillDucks` against the arithmetic. Neither is a
+device, and no device was attached.
+
+### The device answered three of the four (measured 2026-08-21, TLP301 / Android 14 / SDK 34 / arm64, Chrome 113 at 424x439)
+
+A Light Phone III was attached after the PR was opened, so what that PR
+listed as unverifiable was re-checked rather than left as a caveat.
+
+**The whole chain resolves on the device.** `__yj.call("player.Player.
+SystemOwnsVolume", [])` answers `true` — build tag, `platformOwnsVolume`,
+`Player.systemVolume` and the generated binding, end to end. That is the
+one thing the source sweep only approximates, and it took a real arm64
+device because nothing else here compiles the `android` file at all.
+(`GOOS=android GOARCH=arm64 CGO_ENABLED=1 go build ./backend/...` with
+the NDK's clang compiles it in ~40 s and is worth running first; it
+catches a type error but not a wrong constant.)
+
+**The control is absent in both mount points**, on the real engine:
+`.bottom-bar volume-control` is `hidden` with an empty shadow root, and
+so is `now-playing-view`'s. Measured on the device, transport **143px**,
+which is the figure the desktop-headless "after" predicted exactly. The
+art is 75px there rather than 68 because the fixture's `.names` block is
+one line shorter, not because anything differs.
+
+**Nothing persists a level nobody chose, and this is the measurement
+that took some care.** The default (50) surviving proves nothing, since
+50 is also what a fresh row holds. So: force-stop, pull `yj.db`, set
+`player_state.volume = 37`, push it back through
+`run-as … dd` (a `cp` from `/sdcard` is refused — the app sandbox
+cannot read it), relaunch, and drive a queue change to make the row be
+rewritten. Reading it back **the WAL has to be pulled with it** — the
+main file still showed the old `last_track_path` and reads as a write
+that never happened. With `yj.db-wal` beside it: `last_track_path` is
+the new track, so `saveState` ran, and `volume` is still **37**.
+
+**The duck cannot be verified on this device, and now for a stated
+reason rather than for want of hardware.** `WailsForegroundService`
+builds its `AudioFocusRequest` without `setWillPauseWhenDucked` on
+API >= 26, so the framework attenuates the stream itself and never
+delivers `AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK`. The device's own log
+says so: `MediaFocusControl: requestAudioFocus() … AA=USAGE_MEDIA/
+CONTENT_TYPE_MUSIC … req=1 flags=0x0` — no
+`AUDIOFOCUS_FLAG_PAUSES_ON_DUCKABLE_LOSS`. **`minSdk` is 21**, so the
+Go-side duck is not dead code; it is reachable on Android 5.0 to 7.1
+and on nothing newer. Any future "verify ducking on a device" needs one
+of those, and asking for a modern phone will not do it.
+
+Two smaller things from the same session.
+
+**A fresh install downloads the real catalog, and it is 209px of the
+screen while it does.** `YJ_CORE_INDEX_URL` is stubbed in
+`dev-headless.sh` and in CI but is real on a device, so the first
+measurement taken was of a screen with `job-band` on it and the art at
+**0px**. That is not a defect and not #172 — it is the environment.
+`explore.Service.StopIndexBuild` and a relaunch is the clean state.
+
+**The first-run wizard does not dismiss when a library appears by a
+route other than its own** (#175) — it was still up, full-screen and
+intercepting pointer events, after `AddLibrary` succeeded through the
+binding, and was gone after a relaunch. Filed.
+
+## The context menu was clipped on the device, and the fix needed four measurements nothing here could make (measured 2026-08-21, TLP301 / Chrome 113 / 424x439)
+
+#60 had been diagnosed from the Web Awesome source and was right. What
+the device added was the numbers, and three things the reading had not
+reached.
+
+**The clip, reproduced before any code was written.** Long-press on the
+lowest visible track row at 424x439:
+
+| | |
+|---|---|
+| viewport | 424x439 |
+| `.main-panel` | 0 to **318**, computed `contain: content` |
+| menu panel | 191 to **401**, 210px tall |
+| clipped away | **83px, three of seven items** |
+| `wa-popup` computed position | `fixed` |
+| `HTMLElement.prototype.hasOwnProperty('popover')` | **false** |
+| row height | **29px** (against a 44px floor and a 48px ask) |
+
+A screenshot shows the menu sliced off flush with the mini player's top
+edge. Both halves of the diagnosis are therefore measured, not inferred.
+
+**"A dialog escapes containment" was the premise, and it was untested.**
+Every dialog in this app is mounted in `index.html`, *outside*
+`.main-panel` — so nothing here was evidence about a dialog opened from
+inside a view, which is what this change needed. A probe `<dialog>`
+appended to `track-list`'s shadow root and `showModal()`n paints to
+y=439, over the mini player and the tab bar. A top-layer element's
+containing block is the viewport, paint-contained ancestor or not.
+Checking that first cost ten minutes and would have cost a rebuild.
+
+**The UA stylesheet is the thing that makes a naive sheet look wrong.**
+That same probe came out **354px wide on a 424px screen**, centred,
+because a native `<dialog>` carries `max-width: calc(100% - 6px - 2em)`
+and `margin: auto`. `max-width: none` and explicit margins are four
+declarations that are pure undoing.
+
+**A retry loop cannot win against a steal that happens later.**
+`MenuKeyboard` focuses the first item and returns as soon as it lands;
+`wa-dialog` then focuses `[autofocus]` or *itself* on the frame after
+`showModal()`, and it cannot see our first item to prefer it — the
+panel is slotted through `menu-surface`, so the dialog's own
+`querySelector` stops at the `<slot>`. Measured: the sheet opened with
+`document.activeElement` on the `<dialog>` and every arrow key went
+nowhere. Lengthening the retry budget does not help, because the first
+attempt *succeeds*. The surface announcing `menu-shown` after
+`wa-after-show`, and the keyboard re-asserting, is the fix.
+
+**The submenu was made worse before it was made better, and only a
+measurement caught it.** `#playlist-submenu` is a
+`placement="right-start"` flyout anchored to its row. Making the menu a
+full-width sheet moved that anchor to x=0, so the flip put the playlist
+picker at **x −182 to 0 — entirely off-screen**, and "Add to Playlist"
+led nowhere at all. Before the change the anchor row started at x≈245
+and the same flip landed it on screen. It is a `menu-surface` too now
+and stacks as a second sheet. Two lessons: a change that moves an
+anchor changes every flip decision downstream of it, and *the scope I
+declared on the issue was wrong* — I had said I would measure the
+submenu and file it, and the measurement said fix it.
+
+**And the sweep found two call sites the conversion missed.** Twelve
+were converted by hand; `menu-surface.test.ts` reads every source file
+and fails on a `<wa-popup>` outside a three-file allowlist, which
+immediately named `queue-panel`'s add-to-playlist popup (a real menu,
+converted) and `now-playing`'s cover preview (a hover affordance in the
+bottom bar — allowlisted, since a touch device never opens it and
+nothing clips it). A thirteenth menu written as a bare popup would pass
+every tier here and be clipped on the device, which is precisely why
+the guard is a source sweep rather than a rendered assertion.
+
+**What no tier here can see remains the clip itself.** This runner's
+Chromium and CI's WebKit both have the Popover API, so the popup is
+top-layered and correct and a "not clipped" assertion passes on the
+broken build. The specs assert the *mechanism* — that the surface is a
+native `<dialog>` at phone width — which is the same move
+`queue-as-a-screen.spec.ts` makes about containment and for the same
+reason.
+
+## Now Playing was not drawing a small square, it was drawing a crop (measured 2026-08-21, TLP301 / Chrome 113 / 424x439)
+
+#172 handed #51 a design question — whether the album art gets a floor
+with the block scrolling, or whether the screen reflows below some
+height. Measuring it first turned up a defect underneath the question,
+and the defect is bigger than the phone.
+
+**The art was never square.** `aspect-ratio` is specified not to
+re-derive the width when `max-height` clamps the height — unlike an
+intrinsic ratio, which CSS2.1 10.4 preserves under both bounds. So
+`width: min(100%, 60vh)` made the width definite, the ratio derived a
+height from it, `max-height: 100%` clipped that height, and the width
+stayed where it was. `object-fit: cover` then cropped a square cover
+into the band. On the device: **264x53**, a 5:1 strip. #172's own table
+called it "39px of art" and the missing half is that those 39px were
+263 wide.
+
+**And it is not only the phone.** The leftover exceeds the width only
+above ~843px of viewport, so every height from ~500 to ~843 drew a
+crop too — most phones, and any short window. The e2e spec written for
+this fails on the old build at 424x439 (263x39), 390x700 (358x315) and
+900x500 (300x36), and *passes* at 412x869, which is the boundary
+falling exactly where the arithmetic says it should.
+
+**Both maxes with auto sizes is the whole fix**, and it was chosen by
+asking Chrome 113 rather than by reasoning: a probe shadow root at
+column heights of 288, 300, 451, 600 and 800 measured four candidate
+rules. `max-width/max-height: 100%` with `width/height: auto` is square
+at all five; the shipped rule cropped at four; `aspect-ratio` on the
+box cropped at the tallest. A corollary that makes it free: `auto` will
+not upscale past the natural size, and the largest tier `saveCoverArt`
+keeps is 400px, so nothing is lost by never exceeding it.
+
+**The placeholder cannot use that rule and needed its own**, which is
+the part that would have shipped broken. It is not a replaced element,
+so with no intrinsic size auto/auto collapses it to its icon —
+measured at **13x58**, neither square nor the art's size. Three things
+about the rule it did get:
+
+- It is driven from the **height**, which is the axis that binds
+  everywhere this view is reached from.
+- A flex item's automatic minimum is its content, so without
+  `min-width: 0` the icon's own width becomes a floor and the box goes
+  wider than it is tall the moment the row is shorter than the icon —
+  which is exactly the state a job band puts this screen in.
+- **A non-replaced box cannot express "the largest square that fits" at
+  all**, because whichever max clamps does not re-derive the other. The
+  height-driven rule alone went **380x484** at 412x869 — a tall phone,
+  #51's other named device — and `max-height: calc(100vw - 2rem)` is
+  what closes it. That is sound here for the reason `60vh` was not: this
+  is a phone-width detail view, so its content box really is the
+  viewport less the host's own gutters, and it is a *max*, so if that
+  ever stopped being true the failure is a square bounded early rather
+  than a crop. `rem` and not `em` — the box sets `font-size: 3rem` for
+  the icon, so `2em` there is 96px.
+
+**Then the design question, and the reflow is the answer.** The
+stacked layout's budget is fixed — 48px of header, 143px of transport
+since #64, 78px of names, 68px of padding and gaps — so the art gets
+`height - 386`, which is 53px at 439. A floor on the art scrolls the
+transport off the bottom, and "controls never scroll off" is #51's own
+Direction and plan 018's promise. So below 500px the art and the names
+share a row, where the art is bounded by the row's height rather than
+by the column's leftover: **53px to 143px on the device**, measured on
+the shipped build, with nothing scrolling and the transport untouched.
+
+**500 is where the two layouts cross, not a round number.** In a row
+the art is `height - 296` and the names get what is left of 392px, so
+the names hold 176px at exactly 500 and less above it; stacked, the art
+is `height - 386`, which passes 176px at 562. It is keyed on height
+alone rather than on the phone's width because it is an answer to
+vertical room — a 900x450 window has the same problem and the same fix.
+
+Two things the audit found that are *not* this, and are filed:
+**#186**, every control that is not the transport is under the 44px
+floor (the sort direction arrow is 28x21, and `search-trigger` — which
+exists only on a phone — is 40x40), and **#187**, the seek bar's drag
+target is 6px tall.
+
+**What the audit did not find is a reachability failure**, which is
+worth recording because it is the promise plan 018 makes. At 424x439,
+on every view -- the ten primary ones, the queue, `album-details`,
+`artist-details`, Downloads and Autotag -- `documentElement.scrollWidth`
+is 424 against a 424 viewport, no control sits outside a scrollable
+ancestor, and a hit test at each control's centre reaches the control.
+The width work of #57, #62, #55 and #59 holds; what was left was
+vertical, and it was this screen.
+
+**A number measured on the device is not a number CI can assert.** The
+spec's floor on the art's height passed here at 114 and failed in CI at
+**64**, and both are honest: this app is long-lived, so a job staged by
+an earlier spec is still on screen, and `volume-control` renders in a
+browser where it does not on Android. Both are chrome above and below
+the view and both move the leftover. That is the same trap the entry
+above about staged jobs describes, arriving as a *measurement* rather
+than as a stuck job. The assertion is the mechanism now -- in a row the
+art fills the row's height rather than being the leftover -- and the
+53-to-143 stays on the issue, where it was measured.
+
+The probe is worth keeping in mind for the next audit, because two of
+its three checks needed a second pass to mean anything. "Painted
+outside the viewport" flags a horizontally scrolling carousel -- the
+home shelves -- so the real question is whether a *scrollable ancestor*
+can bring the element back. And a hit test at a control's centre flags
+everything below the fold in a scroll container, so it only says
+something once the control is on screen. Both first drafts produced
+long lists of nothing.
+
+## Two traps that cost time on the device, both already written down (2026-08-21)
+
+Recorded because both are in `android-tier.md` and I met them anyway.
+
+**A fresh install downloads the real catalog**, so `job-band` is 103px
+of a 439px screen and every vertical measurement is wrong. Worse, it
+**restarts**: `explore.Service.StopIndexBuild` returns cleanly and the
+job is `running` again within seconds, so it has to be stopped again
+immediately before a measurement rather than once at the start.
+`YJ_CORE_INDEX_URL` is stubbed in `dev-headless.sh` and in CI and is
+real on a device.
+
+**The first-run wizard does not re-check for a library it did not
+create.** Adding one through `library.Library.AddLibrary` over the
+bridge leaves the wizard up with its "Get Started" button correctly
+disabled — it gates on a directory chosen *in the wizard*, and the
+existing-library check runs once, on mount. A reload clears it. Nothing
+is broken; it cost twenty minutes of believing a tap had been swallowed.
+
+## The sheet's scroll fade, and where a scrim may not go (measured 2026-08-23, headless)
+
+#207's answer. The affordance is two background layers on
+`wa-dialog::part(body)` and the conditionality is
+`background-attachment`, not a scroll listener: a cover of the sheet's
+own colour painted at the end of the *content* (`local`) over a shadow
+pinned to the box (`scroll`), so the cover scrolls up and hides the
+shadow exactly when there is nothing more to see.
+
+Measured at 424x360 (which is where a menu overflows on `main`, since
+`main` does not yet carry #67's eighth item — at 424x439 the track
+list's seven items are `scrollHeight` 364 against `clientHeight` 364,
+fitting exactly). Pixel at x=300, dark ramp, `bgElevated` `#343a40`:
+
+| y | before | more below | at the end of the list |
+|---|---|---|---|
+| 330 | 52,58,64 | 50,56,62 | 52,58,64 |
+| 340 | 52,58,64 | 43,48,53 | 52,58,64 |
+| 350 | 52,58,64 | 33,37,40 | 52,58,64 |
+| 359 | 52,58,64 | 22,24,27 | 52,58,64 |
+
+Three things worth keeping.
+
+**A menu that fits draws nothing**, which is the same measurement: at
+424x439 the sheet is flat 52,58,64 to its bottom edge, because with no
+overflow the `local` layer's positioning area *is* the padding box and
+the cover lands on top of the shadow.
+
+**A scrim over a menu row is that row's text surface**, so the 4.5:1
+rule reaches it and this is why the curve is steep rather than linear.
+A row is 48px with its label centred; 32px of scrim already down to a
+quarter strength at 14px puts about 0.06 at the label. Checked on the
+light ramp (`bgElevated` `#e9ecef`, text `#212529`) by overriding the
+two custom properties on `:root`: background at the label 205,207,210,
+which is **9.9:1**. The first draft — a linear 48px at 0.8 — put ~0.375
+on that label, 5.0:1, passing but visibly greyed. The bottom few pixels
+go to ~2.4:1 in either draft and are deliberately below where any
+label of a *fully visible* row sits; a label that lands there belongs
+to the half-cut row, which is the thing being signalled.
+
+**A dark scrim on a dark surface reads far worse in a shrunk screenshot
+than on screen.** The first two probes (24px/0.45, then 32px/0.75) were
+measurably present — 52,58,64 down to 30,33,37 — and invisible in the
+inline preview. Crop the bottom 70px and scale it up before judging;
+the pixel values are the honest answer either way.
+
+## The phone's context sheet is now longer than the phone (measured 2026-08-23, headless at 424x439)
+
+#67 moves two destinations into every row menu, and the track list's
+menu is where that runs out of screen. Measured against the running
+app at the reference viewport, one row selected:
+
+| menu | items | first item top | last item bottom |
+|---|---|---|---|
+| queue panel | 7 | 95 | 431 |
+| track list | 8 | 86 | **470** |
+
+The viewport is 439. So the track list's last item — "Remove from
+Library" — is below the fold. It is **not unreachable**: the sheet is a
+`wa-dialog` whose body is `overflow-y: auto`, measured `scrollHeight`
+412 against `clientHeight` 373, and scrolling it 39px brings that item
+fully into view (383–431). What it has is no *affordance*: nothing on
+screen says the list continues.
+
+Two things worth knowing before adding a ninth item anywhere.
+
+**The limit was already reached, and this is what crossed it.** Seven
+48px rows in a 373px body is 364px — the queue's menu fits with 8px to
+spare and the track list's fitted exactly. Any item added to any of the
+fourteen menus after #60 was going to be the one that overflowed; the
+first one simply happened to be this.
+
+**The measurement has to be taken with a row selected**, since the
+`Go to` items are drawn for a single selection only, and on the *first*
+track of the fixture library — which has no album (`01 Tone A`,
+`02 Tone B`) — only "Go to Artist" appears. That is the 8 above; an
+ordinary track makes it 9.
+
+Filed as its own issue rather than fixed in #67's diff: it is a
+property of the shared sheet (`components/menu-surface/`), not of the
+items.
+
+## The tap highlight is one inherited declaration (measured 2026-08-24)
+
+`-webkit-tap-highlight-color` is an **inherited** property, and an
+inherited property crosses a shadow boundary — so `html { … :
+transparent }` in `index.css` reaches every shadow root in the app and
+no component needs a rule of its own. Measured in the running app
+(Chromium, `app-sidebar`'s `li button`, which is three shadow roots
+from the document): `rgba(0, 0, 0, 0)` with the rule, and
+`rgba(0, 0, 0, 0.18)` with it removed. That 0.18 grey over the bounding
+rect of whatever was tapped is what #54 reported.
+
+The same argument was already spent once and is worth not
+re-deriving: `index.css`'s first rule is `*, *::before, *::after {
+user-select: none }`, which for the same reason already covers the
+shadow roots — #54's Findings ask for `user-select` on interactive
+surfaces and it has been done since before the issue was filed.
+
+**What the highlight was, on the surfaces that had nothing else, is the
+press feedback.** Measured on a track row with the press rule removed
+and the button held down: `rgba(255, 255, 255, 0.05)` — the *hover*
+tint, arriving because the pointer is over the row, which is a
+synthesised hover on a phone and outlives the press. With the rule:
+0.12 while held, and the neighbouring row unchanged. So the press state
+is part of removing the highlight rather than a separate polish item,
+and the hover tints on those same surfaces moved behind
+`(hover: hover) and (pointer: fine)`, which is #68's gate applied to a
+tint rather than to a revealed control.
+
+**`touch-action: manipulation` was considered and not taken.** The
+Findings offer it for the 300ms tap delay; this app's viewport is
+`width=device-width`, which is what removes that delay in Chrome, so
+the stated benefit is not there to win. What it would change is the
+gesture stack #63 tuned by measurement on the device (`pan-y` plus a
+non-passive `preventDefault`), and that is not measurable from here.

.planning/plans/completed/019-android-touch-model.md

@@ -0,0 +1,408 @@
+# 019 — The Android touch model
+
+**Issue:** #63 (`Area/Library-UI`, `Kind/Feature`, `Priority/High`)
+**Depends on:** #60 (bottom-sheet menus) — closed, merged as PR #176
+**Relates:** #67 (inline links into the menu), #71 ("More" nav), #54
+(native feel), #5/#8 (selection, drag to queue — the desktop semantics
+being diverged from)
+**Status:** shipped (phases 1-4). Its one deliberate remainder is #200.
+
+#73 puts #60 first in Phase 4 because it is "the presentation every
+other item needs", and this is the next one. The Direction on #63 asks
+for the interaction model to be designed as one piece before any of it
+is built, because it *reassigns an existing gesture* rather than adding
+one — `utils/long-press.ts` currently owns the 500ms hold, and every
+context menu in the app is downstream of it.
+
+This document is that design. Everything below is a measurement, or an
+argument for one of the choices #63 leaves open.
+
+---
+
+## The mapping
+
+| gesture | pointer is a finger | pointer is a mouse |
+|---|---|---|
+| single tap / click | **play the row** | select the row |
+| double | — | play the row |
+| long press (500ms) | **enter selection mode** | — |
+| right-click | — | context menu |
+| swipe right | **add to queue** | — |
+| drag | reorder / drag to playlist | reorder / drag to playlist |
+
+Three of those are #63's report unchanged. Two are decisions it left
+open, and one is a deliberate divergence.
+
+---
+
+## Decision 1 — the predicate is the pointer, not the platform
+
+#63 says "the row component needs a platform-aware interaction layer
+rather than shared handlers". It needs an interaction layer; it should
+not be platform-aware.
+
+**The question a row has to answer is not "am I on Android" or "is the
+viewport under 600px" but "what made this event".** `pointerType ===
+'touch'`, read off the event that is being handled, which is already
+how `long-press.ts` decides (`if (e.pointerType !== 'touch') return`)
+and is the only such test in the frontend today.
+
+This is #64's rule — the predicate is named after the capability, not
+the platform — and it carries #64's warning with it. Keyed on a width:
+
+- an Android **tablet** at 600px or more gets click-selects /
+  double-click-plays on a touchscreen, which is the exact inversion
+  this issue exists to fix, on the platform it exists for;
+- a **touchscreen laptop** cannot be described at all, because both
+  pointers are live in the same session on the same row;
+- and a narrow desktop window gets phone semantics with a mouse.
+
+Per event, all three are right for free, and there is no second
+declaration of what a phone does — the thing CLAUDE.md declines to add
+every time it comes up.
+
+**Measured, so this is not an assumption about the WebView.** On the
+reference device (TLP301, Android 14, WebView Chrome 113, 424x439),
+driving a real tap with `adb shell input tap`:
+
+```
+[["down","touch",78,94],["touchstart","touchstart",0,0],["up","touch",78,94]]
+```
+
+`PointerEvent` exists, `pointerType` is `"touch"`, `maxTouchPoints` is
+5, and `(pointer: coarse)` / `(hover: none)` both match.
+
+---
+
+## Decision 2 — there is no double-tap, and the number is why
+
+#63 asks for *single tap → play* **and** *double tap → context menu*.
+Those two cannot both be honoured. The first tap of a double tap is
+indistinguishable from a single tap until the interval expires, so
+"tap plays" necessarily becomes "tap waits to find out whether you
+meant something else, then plays". The app already owns that constant:
+`utils/explore-link.ts` holds a navigation for `DOUBLE_CLICK_GRACE_MS
+= 250` for precisely this reason.
+
+**What it would be added to, measured on the device.** Six runs, from
+the play command to the backend's `TrackChanged`:
+
+```
+155, 123, 85, 56, 91 ms          median ~100
+```
+
+So the app's primary interaction is ~100ms, and a double-tap
+discriminator makes it ~350 — **3.5x, of which 250ms is spent
+deliberately doing nothing** — paid on every track anyone ever plays,
+in order to reach a menu.
+
+It is also against the platform's convention, which counts for more
+than usual here because this is the phone build and nothing else:
+long-press is *how you select* on Android (Gmail, Files, Photos),
+double-tap is zoom or nothing, and a list's menu is either the
+long-press sheet or a per-row overflow.
+
+**So the menu and the selection action bar become the same surface**,
+which is the convention and removes a concept rather than adding one.
+Long-press selects the row it was made on and raises the action bar;
+the bar's actions *are* the context menu's actions, contextualised to
+whatever is selected — one row or forty. #60's bottom sheet stays
+behind it as the overflow, so `contextMenuStyles`, `MenuKeyboard` and
+`menu-surface` are reused rather than reimplemented.
+
+---
+
+## Decision 3 — tap-to-play and selection mode ship together
+
+The obvious phase order is "tap plays first, it is the smallest
+change". It is wrong, and the reason is a capability that exists today
+and is easy to miss.
+
+**A touch user can already multi-select**: tap selects (the desktop
+semantics, which a finger currently gets), and the long-press menu then
+acts on the selection. Move tap to play without shipping selection mode
+in the same change and there is a window — a release, if it lands — in
+which selecting forty tracks to add to a playlist is impossible on a
+phone. That is a regression dressed as an increment.
+
+So phase 1 is both, or neither.
+
+---
+
+## What the code looks like now
+
+| surface | how it binds | selection |
+|---|---|---|
+| `track-list` | delegated on the virtualizer: `click`, `dblclick`, `contextmenu`, `dragstart` | `SelectionController` |
+| `queue-panel` | delegated, same shape | `SelectionController` |
+| `playlist-details` | per row | `SelectionController` |
+| `smart-playlist-details` | per row | `SelectionController` |
+
+All four already share `SelectionController`, and all four resolve a
+row from an event by `data-index` / `data-file-path` on the row. So the
+gesture layer has one shape to talk to, and "selection mode" is a flag
+on the controller they already have rather than a fifth concept.
+
+`utils/long-press.ts` is one document-capture listener that synthesises
+a `contextmenu` — the seam that needed no component to opt in. **This
+plan keeps that shape and changes what the gesture means**, which is
+why it is a rewrite of that file rather than a second listener set: two
+document listeners both claiming the 500ms hold is the fault the file's
+own header warns about.
+
+---
+
+## Two measurements that decide the implementation
+
+**`touch-action` is `auto` on both the virtualizer and the rows.** With
+`auto` the browser owns panning on both axes, so a horizontal drag can
+be claimed as a scroll and our gesture ends in `pointercancel`
+mid-swipe. A row that wants a horizontal swipe has to declare
+`touch-action: pan-y`: the browser keeps the vertical pan (which is the
+virtualizer's scroll, and must stay native or the list stutters) and
+hands us the horizontal axis. This is the single most likely way for
+swipe-to-queue to "work in Chromium and not on the phone".
+
+**The row is 424x52 on the device**, so a swipe threshold in px is a
+fraction of a row height, not of a screen.
+
+**And the third one was found by building phase 1 and then running it**
+— it is not something any browser tier can report. Chrome 113's Android
+WebView **fires its own `contextmenu` on a long press**. `long-press.ts`
+stood down when a trusted one arrived, which was right while both paths
+ended in the same place; once a hold can mean selection mode they end
+in different places, and standing down means the gesture silently does
+the *old* thing. Measured, before the fix:
+
+```
+{"log":["contextmenu isTrusted=true"],
+ "state":{"bar":null,"menuActive":true,"selected":1}}
+```
+
+`yj-long-press` was never announced at all, the context menu opened,
+and all 26 tests in the component tier passed — dispatched pointer
+events do not make a browser synthesise a `contextmenu`.
+
+So the browser's event is a **trigger, not a competitor**: the gesture
+is announced from it, and only a component that claims it suppresses
+the native menu. Unclaimed, it propagates untouched. That is the same
+"browser wins" outcome, reached by asking instead of assuming — and
+verified both ways on the device, a track row entering selection mode
+and an album card still opening its menu.
+
+The tier could not *find* it and can *hold* it: a test cannot dispatch
+a trusted event, but this module has always told its own apart by
+identity rather than `isTrusted`, so an untrusted one from a test takes
+exactly the browser's path.
+
+---
+
+## A tier note: this one can be driven, not only measured
+
+`adb shell input tap|swipe` reaches the WebView as real pointer events,
+which the log above is evidence of. So for the first time the Android
+tier can *perform* the thing under test rather than describe the page
+afterwards — a long press is `input swipe X Y X Y 600`, a swipe right
+is `input swipe X Y X+N Y 120`.
+
+Device CSS pixels from device pixels, on this phone:
+`css = (device - 59) / 2.564` vertically, `css = device / 2.564`
+horizontally (measured from the tap above: 200,300 arrived as 78,94).
+
+This does not make the device a spec tier — it does not run in CI and
+`make ui-test` still has to carry the assertions. It makes "does the
+gesture actually fire on Chrome 113" answerable in seconds.
+
+---
+
+## Phases
+
+**Phase 1 — the seam, tap-to-play, selection mode.** `utils/
+touch-gestures.ts` replacing `long-press.ts`: pointer-typed
+recognition of tap / long-press / horizontal swipe, dispatched as
+composed custom events so a delegated listener in any shadow root
+still works. `SelectionController` gains a mode. `track-list` acts on
+tap and enters the mode on long press. The action bar.
+
+**Phase 2 — swipe right to queue**, with the `touch-action: pan-y`
+finding above and a reveal-and-snap affordance. **Shipped**; what the
+device said about it is the section below.
+
+**Phase 3 — the other three surfaces**, which is mostly wiring, since
+they already share the controller. **Shipped**, and it was not entirely
+wiring — see below.
+
+**Phase 4 — what this leaves behind.** The inline `explore-link`s in a
+row are a single-click target inside a row whose single tap now plays;
+that conflict is #67's, and this plan should not pre-empt its answer
+beyond making tap-to-play win on touch. **Shipped.**
+
+## Phase 3 was not symmetric, in two places
+
+**A tap on a queue row plays that position**, not the list. Copying
+`track-list`'s tap — which sets the queue to the list the row is in —
+would rebuild the queue *from* the queue, discarding its source, its
+shuffle order and everything a user had inserted by hand. It reads as a
+no-op and is not one.
+
+**The queue panel has no swipe, deliberately.** A right swipe means
+*add to the queue* everywhere else it exists, and a queue row is
+already in the queue; the only thing it could mean there is *remove*,
+which is the same gesture with the opposite effect one screen away —
+the fault `utils/icon-language.ts` exists to have fixed for glyphs.
+Removing a queue row is on the row itself (the ×), on its bottom sheet
+since #60, and on the selection bar this phase gave it. The assertion
+is that its rows do **not** carry `data-swipe`, so a swipe there cannot
+silently become a second meaning for the app's one horizontal gesture.
+
+And the affordance became `utils/swipe-to-queue.ts` rather than being
+copied twice. Three lists want it; three copies of "how far is far
+enough" is three chances for them to disagree, which is what
+`utils/library-status.ts` and `utils/ownership.ts` each exist to have
+stopped happening. The shared stylesheet is keyed on `[data-swipe]`
+rather than on a class name, because the three lists call their rows
+two different things and the `touch-action` half of the device fix has
+to reach all of them.
+
+## Phase 4 was already true, which is why it is asserted
+
+A claimed tap has its click swallowed at document capture, so an
+`explore-link` inside the row never sees one and tap-to-play wins with
+no rule of its own. Nothing in the suite would have failed if that
+stopped covering the link, and the symptom — tapping a track's *title*
+navigating to its album instead of playing it — is one a phone user
+meets constantly and a mouse user never does.
+
+**Its test was vacuous when written**, in the way this file keeps
+finding: the tap helper dispatched `pointerdown` and `pointerup` and no
+`click`, so there was nothing to swallow and the assertion held on any
+build. It sends the trailing click now, which also strengthened phase
+1's "a tap plays and does not also select". The fixture needed an MBID
+for the same reason — without one the link asks the backend for a local
+album first and gives up when nothing answers, so "it did not navigate"
+was true of a working build and a broken one alike.
+
+---
+
+## What phase 2 measured, which was not what phase 2 predicted
+
+The `touch-action` finding above is **half** of the answer, and
+shipping only that half would have been the exact failure it warns
+about. Driving a real finger with `adb shell input swipe` across a
+track row, three values, all three on the device:
+
+```
+touch-action: auto    pointerdown, 1 move,  pointercancel
+touch-action: pan-y   pointerdown, 2 moves, pointercancel
+touch-action: none    pointerdown, 2 moves, pointercancel
+```
+
+`touchmove` kept firing in all three. So **Chrome 113's WebView
+cancels the pointer stream ~16px into any drag whatever `touch-action`
+says**, and a swipe recognised from `pointermove` — which is what the
+rest of this module is built on — is a swipe that dies 16px in.
+
+The other half is a **non-passive `touchmove` calling
+`preventDefault()`**: with it, the same swipe ran to 12 moves and a
+`pointerup` at full travel. And both halves are required, which was
+measured rather than assumed — with the `preventDefault` in place and
+`touch-action` back at `auto`, the gesture died after **one** move.
+The reading is that `auto` lets the browser commit to a horizontal pan
+on the first move past slop, before any threshold of ours can have
+been crossed, while `pan-y` leaves it undecided long enough for the
+second move to claim it.
+
+`none` is the one value to avoid: the list stopped scrolling at all.
+With the shipped pair, a vertical drag still scrolls the virtualizer
+81px on the same run that a horizontal one survives.
+
+**`draggable="true"` is not a competitor**, which is the other thing
+the device was asked. No `dragstart` fires from a touch drag on this
+WebView at all, so the drag-to-playlist attribute on every row needs no
+pointer-type gate.
+
+### And it found a phase 1 defect that no tier can see
+
+The native `contextmenu` arrives in **either** order, and phase 1 only
+handled one of them. `nativeSeen` covers the browser's menu arriving
+*during* the hold. The reverse — our 500ms timer firing first, a
+component claiming it, and Chrome delivering its own `contextmenu`
+50–70ms *later* — was suppressed by nothing, so the context menu
+opened on top of the selection bar. Measured over four holds:
+
+```
+hold 1  yj-long-press, then contextmenu isTrusted=true   menu open
+hold 2  yj-long-press                                    clean
+hold 3  yj-long-press, then contextmenu isTrusted=true   menu open
+hold 4  yj-long-press                                    clean
+```
+
+Two in four, on the one surface #63 exists to have changed, and
+invisible to both browser tiers because neither synthesises a
+`contextmenu` from a dispatched press. A press that has produced its
+outcome now suppresses a late one whichever branch it took; six holds
+on the fixed build, six clean.
+
+### The rules phase 2 settled
+
+- **A swipe is not a selection.** It queues the row it was made on,
+  unless that row is one of several *explicitly* selected — the same
+  rule the context menu answers with, because a bar reading "40
+  selected" beside a gesture that quietly queues one of them is two
+  answers to one question. It never changes the selection, which is
+  where it differs from a right-click.
+- **Rightward only.** Nothing is bound to a leftward swipe and
+  claiming one would take a gesture away to do nothing with it.
+- **The commit threshold is a fraction of the row** (0.3, floor 72px),
+  because the row is 424x52 on this device and a bare pixel count is a
+  fraction of a row height on one screen and a third of the width on
+  the next.
+- **The affordance is not only a colour** (WCAG 1.4.1, the rule the
+  playing-row marker exists for): the pane carries the queue icon and
+  words, the words change at the threshold ("Add to queue" → "Release
+  to add" → "Added"), and the outcome is announced in a live region.
+- **The row does not move; its cells do.** `.track-row` is
+  `contain: strict` with `overflow: hidden`, so a pane held at the
+  row's original position while the row translates is a pane at a
+  negative offset inside a clipping box and is simply not painted.
+  Sliding the cells needs no wrapper element in a row that is already
+  a grid.
+- **The travel is written to the row's own style, not rendered.** One
+  render at the start, one at the threshold, one at the end; a
+  virtualizer re-rendering every visible row per frame of one finger's
+  travel is the thing `perf.m1` is about.
+
+## Open questions
+
+1. **Does selection mode have an escape other than the bar's own
+   close?** *Settled: Escape, here; back, not here.*
+
+   Escape leaves the mode, from `selection-bar` rather than from each
+   of the four hosts — that element exists only while the mode does, so
+   it is the one place a dismissal can be attached and detached with
+   the thing it dismisses. It is the same documented exception the
+   overlaid queue's Escape is: **a dismissal, not a shortcut**, so it
+   is not a panel-scoped binding.
+
+   The back gesture is the half that is *not* done, and deliberately.
+   The obvious version — `selection-bar` pushing a history entry — is
+   precisely the fault `navStack` was deleted for: the shell owns the
+   stack (#6/#55) and is the only thing that calls `pushState`, so that
+   two stacks cannot disagree about what one press means. Four lists
+   each reaching for `history` is four stacks. It is also wrong on its
+   own terms, since a mode is per-component and a user who enters one,
+   navigates away and returns has an entry for a mode that no longer
+   exists. #55 settled the shape for a *place*; a mode is not one,
+   which is why it could not simply inherit that answer.
+
+   What it wants is one shell-owned register of dismissible surfaces,
+   which would retro-fit the queue overlay, the dialogs and this alike
+   rather than adding a fourth private answer. **#200.**
+
+2. **Does a tap on a row's favourite icon still toggle it in normal
+   mode?** *Settled in phase 1: yes.* A control inside the row keeps
+   its own tap — the gesture is simply not claimed there, so the click
+   behind it falls through untouched. It is the same rule the shortcut
+   service has for a focused control that owns a key, and it is what
+   keeps the 44px favourite target (#56) from becoming a 44px play
+   target. The queue row's × is the second instance of it.

CLAUDE.md

@@ -262,6 +262,26 @@ real store code. A binding carries an **ID**, not a name
 `yellowjacket/backend/home.Service.GetShelves`), so the fake derives
 that map from the generated tree rather than writing it down.
 
+**A test file does not get its own origin, so `setup.ts` clears
+`localStorage` between tests.** `@vitest/browser-playwright` opens one
+BrowserContext per session and runs several files in it one after
+another, so everything a component persists — the track list's sort and
+column widths, the cover size, `now-playing`'s scroll mode — is still
+there when the next file mounts the same component. Which files share a
+tab, and in what order, changes run to run, so the symptom is a spec
+that fails about one test in three and passes every time it is run on
+its own: #138 cost three scheduled runs, one of them a PR whose diff
+held no frontend code at all. Measured on the build before the fix, a
+single full run started **24** tests with storage already set. Two
+things follow. The clear is safe precisely because the leak is
+sequential — files in a session do not overlap, so it cannot wipe
+storage a concurrently-running file is in the middle of using — and it
+belongs in `setup.ts` rather than in the specs that write, because the
+spec that *reads* is never the one that knows. And a spec whose
+assertion depends on an order still **states that order** rather than
+inheriting a default, or the next change to a default is the same
+mystery again.
+
 **`frontend/bindings/` is generated by `wails3`, not `go generate`**, so
 the pre-commit codegen check does not cover it. `make bindings-check`
 (~3.5 s warm, ~20 s on a cold build cache, also a pre-commit hook)
@@ -646,7 +666,11 @@ rather than renaming them.
   level rather than writing through to the volume, so it cannot
   accumulate and nothing persists or emits a level the user did not
   choose — and it only ever fires below API 26, where the framework
-  does not already duck the app itself.
+  does not already duck the app itself. On that platform "the user's
+  level" is a constant, since #64 pins it at maximum and refuses every
+  way to move it; the duck is the one thing that still may, and it
+  works unchanged because it was always an offset applied *to* that
+  level rather than a write of it.
 - `system` — OS-specific paths (XDG on Linux, `%LOCALAPPDATA%` on Windows).
 - `explore` — Catalog search and browse over `explore_index`. See below.
   Its **shelves** (`shelves.go`) are the page Explore shows before
@@ -1089,9 +1113,9 @@ not the fix and cannot be: that function is the `document` listener for
 `navigate`, so it is an infinite loop.
 
 **It is a store rather than an event, because a component that mounts
-after a navigation still has to know.** `bottom-nav`'s "More" drawer
+after a navigation still has to know.** `bottom-nav`'s "More" sheet
 creates its `<app-sidebar>` on open, and that copy had heard no
-`navigate` at all — standing on Albums, the drawer opened highlighting
+`navigate` at all — standing on Albums, it opened highlighting
 Home. An event has no answer for a listener that was not there.
 
 **A detail view is not a view here**, so the destination it was opened
@@ -1192,7 +1216,7 @@ and then vanishing.
 than a general rule about phones.** `PHONE_COLUMN_IDS` is the precedent
 for "what a phone shows is a different question", and it would apply —
 except that `bottom-nav`'s "More" opens the *same* `<app-sidebar>`,
-which filters, so an unfiltered bar would contradict its own drawer one
+which filters, so an unfiltered bar would contradict its own sheet one
 tap away. Which four tabs is still plan 016's committed subset; this
 only removes from it, and "More" is never filtered because it is how
 everything else stays reachable.
@@ -1363,8 +1387,17 @@ against the real components:
   `wa-dropdown-item` sets its `role` in its *own* first update, so a
   `[role^="menuitem"]` query at `updateComplete` finds nothing — which
   reads exactly like a menu that opened and refused to take focus.
-- **`focus()` on a popup that has not positioned itself is a silent
+- **`focus()` on a surface that has not shown itself is a silent
-  no-op**, so the first focus is retried across a few frames.
+  no-op**, so the first focus is retried on a *time* budget rather
+  than a frame count — the thing being waited for is another
+  component's animation. And a retry is not enough on its own for the
+  sheet below: `wa-dialog` focuses `[autofocus]` or *itself* on the
+  frame after `showModal()`, and it cannot see the first menu item to
+  prefer it, because the panel is slotted through `menu-surface` and
+  the dialog's own `querySelector` stops at the `<slot>`. The first
+  attempt therefore *succeeds* and is then overwritten, which no
+  amount of waiting fixes — so the surface announces `menu-shown` when
+  it has settled and `MenuKeyboard.refocus()` re-asserts.
 - **Focus is only taken back if the menu had it.** A click elsewhere
   closes the menu too, and pulling focus to the row the user
   right-clicked a moment ago is worse than leaving it.
@@ -1372,19 +1405,276 @@ against the real components:
   moving focus without setting it leaves the highlight on whichever
   item the mouse last touched.
 
+**And a menu is drawn where it fits: a popup on a desktop, a bottom
+sheet on a phone** (#60). `components/menu-surface/` is that one
+decision. The host renders the panel it always rendered and slots it
+into whichever surface is up, so `ContextMenuController` still drives
+`.active` and `.anchor` as though it were talking to a `wa-popup`, and
+fourteen call sites changed one tag name each and nothing else.
+
+**It is a correctness fix, not a taste one, and the failure was
+measured on the device rather than inferred.** Chrome 113 has no
+Popover API, so `wa-popup` takes its own documented fallback and
+positions with `strategy: "fixed"`; `.main-panel` carries
+`contain: layout style paint`, and paint containment *clips* fixed
+descendants. On the reference device the main panel spans 0-318 of a
+439px viewport while the open menu spanned 191-401 — three of its seven
+items cut off, with no way to reach them. `showModal()` is Chrome 37
+and uses the real top layer, so a dialog is immune by construction.
+
+Seven things about it are load-bearing.
+
+**"Dialogs are fine" needed checking, because every other dialog in
+this app is mounted in `index.html`** — outside `.main-panel` — so it
+was not evidence about one opened from inside a view. A probe dialog
+appended to `track-list`'s shadow root paints to y=439, over the mini
+player and the tab bar, with the contained ancestor still in place. A
+top-layer element's containing block is the viewport, contained
+ancestor or not.
+
+**The sheet has to un-do the UA stylesheet.** A native `<dialog>`
+carries `max-width: calc(100% - 6px - 2em)` and `margin: auto`, which
+drew a 354px panel floating in the middle of a 424px screen.
+`max-width: none` plus explicit margins is what makes it a sheet.
+
+**The row sizing lives in `contextMenuStyles`, not in the component.**
+The panel is the *host's* light DOM — it stays in the host's shadow
+root, so only the host's stylesheet can reach it. `menu-surface` puts
+`data-sheet` on the panel and that shared stylesheet does the rest,
+which is how fourteen menus went from 29px rows to 48px ones in one
+edit.
+
+**A dismissal has to travel back.** `wa-dialog` closes itself on
+Escape, which would leave the controller believing the menu is open —
+and the failure mode is not a stuck sheet but the *next* long-press
+doing nothing, which reads as the gesture breaking. `menu-dismiss` is
+that signal; the three surfaces that do not use `ContextMenuController`
+bind it themselves.
+
+**A sheet that scrolls says so, and `background-attachment` is what
+asks whether it does** (#207). The sheet is capped at 85vh — a surface
+covering the whole screen is a page, not a sheet — so a long menu's
+body scrolls, and for three phases it scrolled *silently*: measured at
+424x439, eight items ended at y=470 with the fold at 439, and where the
+cut lands on a row boundary the sheet ends in a clean edge that reads
+as the end of the list. The fade is two background layers on
+`wa-dialog::part(body)` — a shadow pinned to the box (`scroll`) under a
+cover of the sheet's own colour painted at the end of the *content*
+(`local`), which scrolls up over the shadow exactly when there is
+nothing more to see. So it is absent on a menu that fits, present the
+moment one does not, and gone again at the end of the list, with no
+scroll listener and nothing reaching into `wa-dialog`'s shadow root for
+the scroller. **The curve is steep because the rows under it stay
+live**: a scrim over a menu item is that item's text surface, and the
+4.5:1 rule applies to it — 32px already down to a quarter strength at
+14px spends its weight below the last legible label, measured at 9.9:1
+on the light ramp, whose `bgElevated` is `#e9ecef`.
+
+**The playlist submenu is a sheet too, and it had to be.** It is a
+`placement="right-start"` flyout, and making the menu full-width moved
+its anchor — measured at x −182 to 0, entirely off-screen, so "Add to
+Playlist" led nowhere. It stacks as a second sheet over the first,
+which is also why `menu-shown` does not re-assert focus while the
+submenu is open.
+
+**And which call sites exist is swept, not remembered.** A thirteenth
+menu written as a bare `<wa-popup>` works perfectly in every tier here
+and is clipped on the device, so `menu-surface.test.ts` reads the
+source and fails on one outside a three-file allowlist —
+`menu-surface` itself, `job-indicator` (in `.top-bar`, which no
+ancestor contains — the contrast that proved the diagnosis on #62) and
+`now-playing`'s cover preview (a hover affordance, which a touch device
+never opens). **The sweep found two of the fourteen**; twelve were
+converted by hand.
+
 **And a menu opens from a finger, through the event it already has.**
-`utils/long-press.ts` is one document-capture listener installed once
+`utils/touch-gestures.ts` is one document-capture listener installed
-from `index.ts`: a touch that holds still for 500 ms dispatches a
+once from `index.ts` — `utils/long-press.ts` until #63 replaced it,
-synthetic `contextmenu` at the touch point, so all six components that
+rather than adding a second listener claiming the same 500 ms hold. It
-bind one — delegated on a virtualizer, per row, per card — gained the
+**announces** rather than acts: `yj-tap`, `yj-long-press` and
-gesture without changing. The target is `composedPath()[0]` rather than
+`yj-swipe-start` are composed and cancelable, and a component claims
+one with `preventDefault()`. That is what let #63 reassign the hold
+without touching one of the fourteen context menus: an *unclaimed*
+`yj-long-press` still becomes a synthetic `contextmenu`, so all six
+components that bind one — delegated on a virtualizer, per row, per
+card — behave exactly as they did, and only the lists that opt in get
+selection mode. The target is `composedPath()[0]` rather than
 `elementFromPoint`, which stops at the outermost shadow host and so
-reaches a delegated listener and no per-row one; a browser that fires
+reaches a delegated listener and no per-row one; and the click that
-its own long-press `contextmenu` (Chromium does, WebKit and the WebView
+ends a *claimed* gesture is swallowed, keyed on the gesture rather than
-vary) wins, ours being told from theirs by **identity** rather than
+on a time window so the first tap on the menu it opened is not eaten
-`isTrusted`, since no test can dispatch a trusted event; and the click
+too.
-that ends the gesture is swallowed, keyed on the gesture rather than on
+
-a time window so the first tap on the menu it opened is not eaten too.
+Three things about it are load-bearing, and all three were found on the
+device rather than in a tier.
+
+**A browser that fires its own long-press `contextmenu` is a trigger,
+not a competitor.** Chromium does, WebKit and the WebView vary. The old
+rule was to stand down when a trusted one arrived, which was right
+while both paths ended in a context menu and is wrong the moment a hold
+can mean something else — standing down silently does the *old* thing.
+So the gesture is announced from the native event, and only a component
+that claims it suppresses that event. Ours and the browser's are told
+apart by **identity** rather than `isTrusted`, since no test can
+dispatch a trusted event.
+
+**That arrives in either order, and both have to be handled.** The
+native `contextmenu` mid-hold is one case; the other is our own 500 ms
+timer firing first and Chrome delivering its menu **50–70 ms later**,
+which nothing suppressed — measured over four holds on the reference
+phone, two took that order, so the context menu opened over the
+selection bar intermittently, on the one surface #63 changed. A press
+that has produced its outcome therefore suppresses a late
+`contextmenu` whichever branch it took.
+
+**A horizontal swipe runs on touch events, and needs two things that
+look like one.** Chrome 113's WebView cancels the *pointer* stream
+~16 px into any drag — measured at `auto`, `pan-y` and `none` alike,
+one or two `pointermove`s and then `pointercancel`, while `touchmove`
+kept firing throughout. So the recogniser is `touchmove`, the surface
+declares **`touch-action: pan-y`** *and* a claimed swipe calls
+**`preventDefault()`** on a non-passive listener. Neither works alone:
+with the `preventDefault` in place but `touch-action` back at `auto`
+the gesture died after one move, because `auto` lets the browser commit
+to a horizontal pan before any threshold can be crossed. `none` is the
+value to avoid — it takes the list's own vertical scrolling with it.
+**Both are correct in Chromium either way**, which is why this is
+written down rather than tested. The tie breaks toward scrolling, in
+that order: vertical drift past the tolerance vetoes the swipe for the
+rest of the press (a scroll that curves is still a scroll), and a
+gesture that is not *strictly* more horizontal than vertical is the
+scroller's.
+
+**And what a finger *means* on a row is the inversion of what a mouse
+means, decided per event** (#63). A click selects and a double-click
+plays; a tap **plays** and a hold enters **selection mode**, in which a
+tap toggles. The predicate is `pointerType`, never a viewport width and
+never a platform flag — #64's rule, and with #64's warning: keyed on a
+width, an Android tablet over 600px gets desktop semantics on a
+touchscreen, a touchscreen laptop cannot be described at all, and a
+narrow desktop window gets phone semantics with a mouse.
+
+There is deliberately **no double-tap**, which #63 asked for. The first
+tap of one is indistinguishable from a single tap until the interval
+expires, so tapping would have to wait `DOUBLE_CLICK_GRACE_MS` before
+acting — 250ms on top of a measured ~100ms play, 3.5x the app's primary
+interaction, to reach a menu a hold already reaches. So the menu and
+the action bar are the same surface: `components/selection-bar/` is
+presentational (a count and a list of actions, no store, no selection),
+`SelectionController` carries the mode for all four selecting surfaces,
+and #60's bottom sheet is the overflow behind "More" — so
+`contextMenuStyles`, `MenuKeyboard` and `menu-surface` are reused
+rather than reimplemented.
+
+Three things about it are load-bearing. **A control inside a row keeps
+its own tap**: the gesture is simply not claimed there, so the click
+behind it falls through, which is what stops the 44px favourite target
+(#56) becoming a 44px play target — the queue row's × is the second
+instance. **A swipe right queues**, and its affordance is
+`utils/swipe-to-queue.ts` once rather than in each of the three lists
+that draw it: the row does not move, its *children* do (a row here is
+`contain: strict` with `overflow: hidden`, so a pane held at the row's
+original position while the row translates is at a negative offset
+inside a clipping box and is not painted), the travel is written to the
+row's own style rather than rendered, and the threshold is a fraction
+of the row because the row is 424x52 on the reference device. **The
+queue panel takes the tap and the hold and refuses the swipe**, because
+a right swipe means *add to the queue* everywhere it exists and a queue
+row is already in it — the only thing it could mean there is *remove*,
+which is the same gesture with the opposite effect one screen away.
+A tap there plays that *position*, too: setting the queue to the queue
+reads as a no-op and discards its source, its shuffle order and
+anything inserted by hand.
+
+Escape leaves the mode, from `selection-bar` rather than from each
+host, since that element exists only while the mode does — the same
+exception the overlaid queue's Escape is, *a dismissal, not a
+shortcut*. The platform's back gesture deliberately does **not** reach
+it: the shell owns the history stack and four lists each reaching for
+`history` is four stacks, which is the fault `navStack` was deleted
+for. That wants one shell-owned register of dismissible surfaces, which
+is #200.
+
+**A control revealed by `:hover` is gated on the device having hover,
+and which way round depends on whether it is the only route to its
+action.** The gate itself is not optional: a touch long-press
+synthesises a hover state in the WebView, so every one of these flashed
+into view during the 500 ms hold above — a control appearing because
+the user was reaching for a different one. Where the action is reachable
+another way the control is **absent** on a touch device (the home card's
+play button, #68; the queue row's remove, which the row's bottom-sheet
+menu carries since #60), and that is `display: none` outside
+`(hover: hover) and (pointer: fine)` rather than `opacity: 0` or
+`visibility: hidden`, both of which leave a button holding its hit area
+and its place in the accessibility tree. Where the control is the
+**only** route it is instead always visible under
+`@media not all and (hover: hover)` — `track-details`'s cover-art
+overlay and remove, `shortcut-capture`'s reset (#137) — because hiding
+it takes the action away entirely.
+
+**Always-visible is not the same as always-in-the-way.** The cover-art
+overlay is `inset: 0` at 50% black, which is fine as a hover state and
+is not fine as the permanent appearance of the artwork being edited —
+and it is only a *hint*, since `.cover-art-edit` carries the click and
+tapping the art always worked. Off hover it becomes a corner chip in
+the remove button's own language. The × beside it stays full-size,
+because that one really is the only route to its action.
+
+One thing to know before checking either: **no *committed* tier renders
+as a touch device.** CDP's `Emulation.setEmulatedMedia` does not reach
+the component tier's iframe, and the e2e projects are Desktop Chrome
+and Desktop Safari, neither of which has touch — a Playwright project
+using a mobile descriptor would report `hover: none`, so this is a
+choice not to carry one rather than a thing that cannot be done. So
+`hover-affordance.test.ts` asserts the *parsed stylesheet* — which rule
+sits inside which media query — and says so; the regression it exists
+for is someone hoisting a rule out of its query as a tidy-up, which
+nothing on a desktop renders differently.
+
+**The web view's own tap highlight is gone, and what replaced it is a
+press state** (#54). `-webkit-tap-highlight-color` is an *inherited*
+property, so one declaration on `html` in `index.css` reaches every
+shadow root in the app and takes away the grey box a phone drew over
+the bounding rect of whatever was tapped — measured at
+`rgba(0, 0, 0, 0.18)` with the rule removed. `user-select` is the same
+argument and was already done: `index.css`'s first rule is `*, *::before,
+*::after { user-select: none }`, which reaches the shadow roots for the
+same reason.
+
+Three things about it are load-bearing.
+
+**Removing the highlight removes the only touch feedback several
+surfaces had**, so the press state is part of the same change rather
+than a later polish item: the four lists' rows, `bottom-nav`'s tabs,
+`app-sidebar`'s destinations (which are also the phone's "More" sheet)
+and the shared `contextMenuStyles` menu item all take
+`--yj-press-overlay` on `:active`. The cards already had one
+(`transform: scale(0.97)`) and are untouched.
+
+**A press selector carries a state class or it does nothing where it
+matters.** A row is `.track-row.selected.active`, so a bare
+`.track-row:active` is one class short of it and the press is invisible
+on exactly the row a phone is most likely to press — the one it has
+just selected. The rule is last and lists `.selected:active` /
+`.active:active` beside the bare form.
+
+**And the hover tints on those same surfaces moved behind
+`(hover: hover) and (pointer: fine)`**, which is #68's gate applied to
+a tint rather than to a revealed control and for the same mechanism: a
+hold synthesises a hover in the WebView, so an ungated tint arrives
+because a finger touched the row and stays there after it has gone —
+measured, since with the press rule removed a held row reads
+`rgba(255, 255, 255, 0.05)`, the hover tint, rather than nothing.
+`touch-action: manipulation` was considered and declined: the 300ms
+delay it is offered for is already absent on a `width=device-width`
+viewport, and what it would really change is the gesture stack #63
+tuned by measurement on a device this session cannot measure.
+
+The split of tiers is `hover-affordance.test.ts`'s: `press-feedback.
+test.ts` reads the parsed stylesheet, because `:active` cannot be
+forced there either, and `native-touch-feel.spec.ts` *measures* — it
+holds the button down on a real row of the real list, and it is the
+only tier that loads `index.css` at all.
 
 Three lists had no focused row to open a menu *from* — the queue panel
 and both playlist detail views — and gained a roving tab stop through
@@ -1584,7 +1874,7 @@ listing the destinations again — but rendering it unconditionally put a
 second copy of every `data-testid="nav-*"` in the DOM, and 30 existing
 specs failed with "strict mode violation: resolved to 2 elements" on a
 desktop viewport where the element is not even visible. It renders only
-while the drawer is open, and `bottom-nav.test.ts` asserts its absence
+while the sheet is open, and `bottom-nav.test.ts` asserts its absence
 before that.
 
 **The tab bar is four destinations and a way to the rest.** Three to
@@ -1593,6 +1883,33 @@ is 32px each. Which four is plan 016's committed subset, and everything
 else — Settings included, because a phone still needs it — is behind
 "More".
 
+**And "More" rises from the bottom, on #60's sheet rather than a
+second one** (#71). It was a `wa-drawer placement="start"`: a 200px
+column of a 424px screen, opening away from the thumb that asked for
+it, with the rest of its 400px band empty. It is the *same element*
+with `placement="bottom"` and `without-header`, which is what keeps
+the change to where it comes from — `wa-drawer` renders a native
+`<dialog>` and opens it with `showModal()`, so #60's containment
+finding carries over with nothing new to prove, and the focus trap,
+Escape, tap-outside and `wa-after-hide` all come along. Measured at
+424x439: 424 wide, 373 tall (85vh, so there is an outside to tap),
+48px rows.
+
+Three things about it are load-bearing. **The sidebar is mounted
+rather than re-listed as data**, which the issue offers as the
+alternative: the shell's own `<app-sidebar>` is `display: none` below
+600px rather than removed, so a second list drawing `nav-*` handles is
+the duplication above, and it would be a second place to add the next
+view to. **There is one scroller, and it is the sheet's body** — the
+reported "only part of the screen scrolls under my finger" is three
+nested ones (the dialog, its body, and the sidebar's own
+`overflow-y: auto` host), so which box a drag moves depends on where
+the finger landed; `overscroll-behavior: contain` is the other half.
+And **`expanded` means the host owns the box, not just the labels**:
+`app-sidebar` writes an *inline* width and caps itself at 400px, which
+beats any rule the host could write, so the width, the scrolling and
+the mouse-only resize handle all follow that attribute.
+
 **There are three supported size bands, and the queue is part of the
 promise.** Plan 018 (#24) wrote them down: **Phone** below 600 (bottom
 nav, reflows, fits 320px exactly), **Compact** 600–899 (icon sidebar),
@@ -1725,9 +2042,140 @@ where the zero value has to be the intended answer, so an existing
 `config.toml` with no key gets the new default without a migration.
 Inline, the icon becomes the mute toggle and is named after that action
 rather than after the state, because with the slider beside it there is
-nothing left to disclose. It stands down below 600px whatever the
+nothing left to disclose. The bar's copy stands down below 600px, which
-setting says — that is about the platform rather than preference, and
+is about *room*: five controls and a slider do not fit a 360px bar, and
-is why `mediacontrols`' Android handler implements no volume callback.
+`now-playing-view` is where seeking and volume go on a phone.
+
+**Whether there is a volume to control at all is a different question,
+and it is asked of the player** (#64). On Android the hardware keys are
+the volume control and the framework mixes our stream against the
+device level, so `player`'s own level is pinned at maximum, `SetVolume`
+/ `ChangeVolume` / `MuteToggle` are refused, and `volume-control`
+renders `nothing` — in both of its mount points, at every width.
+`mediacontrols`' Android handler implementing no volume callback is the
+same fact one layer down.
+
+Five things about it are load-bearing.
+
+**It could not be a width, and that is not a preference.** Every other
+stand-down rule in this app is keyed on a viewport, because a width is
+what a browser can answer and what every tier can test. This one is a
+property of the build: keyed on width, an Android *tablet* at 600px or
+more draws the bottom bar's slider over a pinned level — a control that
+cannot act, on exactly the platform the rule exists for, which
+`library-status-indicator` already settled is worse than none. The
+same rule is wrong in the other direction below 600px, where a narrow
+desktop window has no hardware keys to fall back on.
+
+**The predicate is named after the capability, not the platform.**
+`SystemOwnsVolume` is what the frontend asks; `platformOwnsVolume` is
+the one build-tagged constant behind it, in two files that declare
+nothing else. That is `mediacontrols`' split with
+`androidpayload.go`'s reasoning: a tagged file is compiled by nothing
+`make lint` or `make test` runs, so everything decidable off a phone is
+decided against `Player.systemVolume`, a field a test sets either way.
+The frontend's absent branch is therefore testable in the component
+tier with a stubbed binding, and the constant itself is covered by a
+source sweep plus, once, a real arm64 device answering `true` — which
+is the only tier that compiles the `android` file at all.
+
+**Mute goes with it, because it is a level of zero by another name** —
+and because with no control rendered it is the one state on such a
+platform the user could not get out of.
+
+**Nothing persists a level nobody chose.** The maximum the player runs
+at is synthetic, so `restoreStateLocked` *remembers* the stored volume
+instead of applying it and `saveState` writes that same value back.
+The alternative — a second query that omits the column — buys nothing
+and is a second write path to keep in step.
+
+**And ducking is untouched, which is what makes the pin safe.**
+`SetDuck` applies its attenuation by re-applying the *user's* level
+through `setVolumeLocked`, so pinning that level to maximum leaves the
+offset arithmetic exactly as it was. It is the only thing that may move
+the output on such a platform, and it is the one volume-shaped path
+that is not refused.
+
+One thing to know before anyone offers to test it on a phone: **the
+duck is unreachable above API 25.** `WailsForegroundService` builds its
+`AudioFocusRequest` without `setWillPauseWhenDucked` from Oreo, so the
+framework attenuates us itself and never sends
+`AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK` — a device confirms it by logging
+`requestAudioFocus() … flags=0x0`. `minSdk` is 21, so this is live code
+rather than dead, on Android 5.0 to 7.1 and nowhere else.
+
+**And below 600px that bar carries three controls, not five** (#59).
+Shuffle, repeat and the queue button leave it; what is left is art,
+title/artist, favourite, and prev/play/next. `player-controls` is one
+component in two places and **the context is a property rather than a
+media query**, which is the exception to the rule two paragraphs down:
+on a phone the bar wants three controls and `now-playing-view` wants
+five, larger still, *at the same viewport* — so the host states the
+context and the viewport states the size band, and neither alone can
+express it. Sizes come from `--yj-control-*` custom properties set per
+context; play/pause alone goes above the 44px floor, because a row of
+identical squares says every action is equally likely and that is not
+true of play. Measured before #56: every one of them was **33×21px**,
+and the mini bar's favourite was **18×14**, the smallest control in the
+app.
+
+Four things about it are load-bearing.
+
+**The phone draws three buttons rather than hiding two**, from
+`matchMedia` — `job-band`'s pattern, and the rule that a decision about
+whether an element *exists* is not a stylesheet's to make. A
+`display: none` control is still in the shadow root and still something
+a positional query finds, so "the phone has three controls" would have
+been true of the pixels and false of the element.
+
+**Removing a control is only allowed because it is still reachable.**
+Plan 018's matrix promises no action is unreachable at any supported
+size, and all three are on `now-playing-view`, one tap away through the
+mini player's art. That promise is what `phone-transport.spec.ts`
+asserts — it walks the route — rather than counting buttons.
+
+**So the route to Now Playing must not depend on what is playing**, and
+it did. `now-playing` renders two branches and the no-track one had no
+`.expand` button on its placeholder, so with nothing loaded there was
+no way to the full-screen view — which, once the queue button left the
+bar, made the *queue* unreachable. The queue is persisted across
+restarts, so "tracks queued, nothing playing" is a state the app
+launches into.
+
+**The desktop bar is untouched and a spec says so with a literal.**
+Both issues are `Platform/Android`. The trap is that a `<button>` does
+not inherit its font from its parent — the UA stylesheet gives it one —
+so a generic `font-size: inherit` is not the no-op it reads as: it took
+every desktop button from 33×21 to 36×24, silently. The sizes are
+asserted as `'33x21'` rather than as a range, because the regression
+was three pixels.
+
+**What that bar lost is how far through the song it is, and
+`<player-progress-line>` is where it went** (#58). Plan 016 B2 took the
+seek bar off the phone's transport, so the one thing a mini player is
+expected to say without being opened had nowhere left to be said. It is
+a 2px line on the border between the mini player and the tab bar: the
+**shell's** element and its own `auto` grid row between `bottom-bar`
+and `bottom-nav`, because those two are separate components and either
+one drawing it means reaching into the other's box for two pixels.
+
+Four things about it are load-bearing. **It never counts** — the fill is
+`scaleX()` off the same `PlaybackPositionChanged` the seek bar renders,
+with the same `trackChangeId` and `seq` guards and an interval that is
+stopped and restarted by every report, which is the rule that exists
+because a local clock drifted 30 s away across four keyboard seeks.
+**It is not a control and cannot become one**: `aria-hidden` on the host
+and `pointer-events: none` throughout, because Now Playing's seek bar
+is what announces the position and a 2px strip on the top edge of the
+tab bar is exactly where a thumb aiming at a tab lands. **It renders
+nothing above 600px**, from `matchMedia` rather than a media query, for
+`job-band`'s reason plus one of its own — a stylesheet cannot stop a
+1 Hz interval running for the life of every desktop session about a
+line nobody can see. And **its phone rule sits at the foot of
+`index.css`, beside `job-band`'s**, not in the phone block above: a
+media query adds no specificity, so a `display: block` written before
+the `display: none` that takes it out of the desktop grid loses to it
+and the line never appears at any width, silently.
 
 **900 is the worst desktop width, not the 800×600 minimum.** The
 sidebar collapses to icons *below* 900, so the main panel is 843px at
@@ -1826,9 +2274,26 @@ one that closes the queue — the reported defect moved one press later,
 which looks exactly like a press that did nothing.
 
 **And the way out is 44px on a phone.** With the panel spanning the
-whole width the scrim has no uncovered pixels at all, so the close
+whole width there is no scrim there at all, so the close button is the
-button is the only pointer route out of a full-screen surface; it was
+only pointer route out of a full-screen surface; it was **25×21px**.
-**25×21px**.
+
+**The scrim is drawn only where it can be tapped** (#171). Below 600px
+`.panel-content` is `width: 100%`, so the scrim sat entirely underneath
+an opaque panel — measured at 424×439, host, panel and scrim all
+424×318 — dimming nothing and dismissing nothing while wearing
+`cursor: pointer`. #24's tap-outside-to-close cannot exist on a surface
+with no outside, and the screen above is what answers it instead: back,
+and a 44px close button. The alternative — a gutter, which is the
+drawer pattern — was declined, because it buys the affordance by taking
+width off a full-screen surface on a 424px viewport. Two things about
+it are load-bearing. Its **existence** is `matchMedia`, not
+`display: none`, on `job-band`'s rule: a hidden scrim is still an
+element carrying the dismissal handler. And **the 600–899 band is
+untouched**, where the panel is a 320px column of a wider content area
+and the scrim has real uncovered pixels — which is why the e2e half
+asserts *absence* at 424×439 rather than clicking, since a phone-width
+case that clicks the scrim's centre hits the panel and passes on the
+broken build.
 
 What this does **not** fix is `page-header` overflowing on its own:
 at 900×600 "New Smart Playlist" is still clipped to 114 of 162px with
@@ -1860,6 +2325,54 @@ toggled from `index.ts` would be a second expression of the same fact.
 The view therefore carries its own queue button, because that button
 lives in the bar it hides.
 
+**And below 500px of height its art and its names share a row** (#51).
+The stacked arrangement's budget is fixed — 48px of header, 143px of
+transport since #64, 78px of names, 68px of padding and gaps — so the
+art gets `height - 386`, which at the reference device's 424x439 is
+**53px**: the one thing a Now Playing screen exists to show, smallest
+on it. #172 named the two ways out and this is the second, because the
+first — a floor on the art with the block scrolling — scrolls the
+transport off the bottom, and *controls never scroll off* is #51's own
+Direction and plan 018's promise. Sideways the art is bounded by the
+row's height instead of by the column's leftover: **53px to 143px**,
+measured on the device, nothing scrolling, the transport untouched.
+
+Three things about it are load-bearing.
+
+**500 is where the two layouts cross rather than a round number.** In a
+row the art is `height - 296` and the names get what is left of 392px,
+so the names hold 176px at exactly 500 and less above it; stacked, the
+art is `height - 386`, which passes 176px at 562. Below 500 the row is
+the bigger art *and* the readable one — above it the column is, which
+is why a tall phone keeps the arrangement it has. It is keyed on height
+alone and not on the phone's width, because it answers vertical room: a
+900x450 window has the same problem and the same fix.
+
+**The art was not a small square, it was a crop, and that was never
+only the phone.** `aspect-ratio` is specified not to re-derive the
+width when `max-height` clamps the height — unlike an intrinsic ratio,
+which is preserved under both bounds — so a definite `width: min(100%,
+60vh)` kept its width while the height was clipped, and `object-fit:
+cover` cropped a square cover into the band: **264x53** on the device.
+The leftover exceeds the width only above ~843px of viewport, so every
+height from ~500 to ~843 drew one too. `max-width`/`max-height: 100%`
+with `width`/`height: auto` is the fix and is the replaced-element
+path; it also never upscales past the natural size, and the largest
+tier `saveCoverArt` keeps is 400px, so nothing is lost.
+
+**The placeholder needs its own rule, and a non-replaced box cannot
+express this one.** With no intrinsic size, auto/auto collapses it to
+its icon (13x58, measured). It is driven from the height instead, with
+`min-width: 0` because a flex item's automatic minimum is its content —
+without it the icon's width becomes a floor the moment the row is
+shorter than the icon, which is exactly what a job band does to this
+screen. And since whichever max clamps does not re-derive the other, a
+height-driven box goes **380x484** on a tall phone; `max-height:
+calc(100vw - 2rem)` closes it, which is sound here for the reason
+`60vh` was not — this is a phone-width detail view, so its content box
+really is the viewport less the host's gutters, and it is a *max*, so
+the failure mode is a square bounded early rather than a crop.
+
 **The playing row is a shape, not a hue.** `track-list` and
 `queue-panel` draw a `::before` triangle in each row's own left
 padding, plus `aria-current` — before, both rows were a background tint
@@ -1934,6 +2447,31 @@ a list or a detail view:
   and dropped if a second click arrives, because the title is the
   widest thing in a row and double-clicking a row plays it. Rows do
   not need to know links exist.
+
+  **Below 600px a name is not a link, and the row's menu is where it
+  went** (#67). Every sentence above is a *desktop* compromise: the
+  double-click grace means nothing on touch, a few characters of text
+  is not a touch target, and since #63 a claimed `yj-tap` has its click
+  swallowed, so the link was unreachable as well as fiddly. The rule is
+  in the utility rather than at twenty call sites, and
+  `utils/go-to-menu.ts` is the other half — "Go to Artist" / "Go to
+  Album", drawn under exactly the condition the link is not, from
+  `explore-link`'s own exported routing so an untagged artist reaches
+  the library page by the same lookup.
+
+  Three things about it are load-bearing. **Suppressing a link without
+  a menu behind it is not a smaller affordance**, it is a destination
+  the phone cannot reach — so `keepOnPhone` is the documented exception
+  for the three surfaces with no row menu (`now-playing-view`,
+  `explore-album-details`' header credit, `top-results-row`), and
+  nothing else may pass it. **One row or none**: the items are the Play
+  item's rule one step on, since "go to the album" of five different
+  albums means nothing. And **there is no "Go to Genre"**, because
+  there is no genre link anywhere to lose — that would be new
+  navigation rather than a replacement, and belongs in its own issue.
+  `track-list` is the one list that gains rather than moves: its phone
+  column set stacks title over artist as plain text already, so those
+  names have never been links there.
 - **`<catalog-scope-notice>`** is how a detail page admits what it is
   showing: catalog data (silent), a library stand-in while a fetch is
   in flight, library-only because the entity has no MBID, or a failed/
@@ -2147,11 +2685,38 @@ Five things about it are load-bearing, and four of them fail silently:
   correctly. Confidently wrong is worse than absent here, which is the
   same rule `Known` exists for.
 
-One gap this did not close, and it is older: **`dhowden/tag` has no
+One gap this did not close and #104 did: **`dhowden/tag` has no RIFF
-RIFF reader**, so nothing the tag writer puts in a WAV's `id3 ` chunk
+reader**, so nothing the tag writer put in a WAV's `id3 ` chunk was
-is visible to `metadata.ExtractTags` — not the totals and not the title
+visible to `metadata.ExtractTags` — not the totals and not the title
-either. `wav_test.go` reads that chunk itself, which is why no test
+either, on files the app itself had just tagged. `wav_test.go` read
-ever noticed.
+that chunk itself, which is why no test noticed: a round trip asserted
+through the writer's own parser is a test of the writer.
+
+`backend/riff` is where the container is now read, and it is its own
+package because the alternative is an import cycle — `tagwriter`
+imports `metadata`, so `metadata` cannot reach back for `parseRIFF`.
+`backend/tagtotals` is the precedent.
+
+Three things about it are load-bearing. **The two readers are
+deliberately different**: `Parse` holds every chunk in memory, which is
+what rewriting a file needs, and a WAV's audio *is* a chunk — so the
+scan path uses `ID3Chunk`, which seeks over what it is not looking for.
+**The container decides, before `tag.ReadFrom` rather than after it
+fails**, because that library's last resort is an ID3v1 trailer and a
+WAV carrying both would otherwise be read by the wrong one. And **an
+untagged WAV is a file with no tags, not a file with a problem**: no
+chunk, an RF64 container or a tag holding no frames all read as empty
+metadata with no `TagReadWarning`, since the scanner's filename
+fallback is the right answer and a warning would put a fault on a file
+that has none.
+
+The gap was pinned by a test that said so, which failed the moment the
+reader learned and carried the instructions for what to update in its
+own comment. So it is deleted, `TestFixturesMatchManifest` no longer
+skips `wav`, and `totals_test.go`'s WAV case goes through
+`metadata.ExtractTags` like the other three formats. The fixture
+library's two WAV tracks scan with their tags and their cover now,
+which is a change to what every seeded tier sees.
 
 **The absence is what gets marked, not the presence.** The tracklist
 put a green tick against every owned track and a legend underneath
@@ -2309,6 +2874,31 @@ missing half; `catalogFailed` is the only route to `unavailable` now,
 and the timer is a 60 s backstop for a genuine hang rather than the
 verdict.
 
+**On a phone that page is one scroll container, and the header is in
+it** (#66). It was built as a fixed header over a scrolling tracklist,
+which is the desktop arrangement: at the reference device's 424×439 the
+header owned **253 of the panel's 318px** and the list scrolled inside
+the 64 that were left. Below 600px the *host* is the scroller and
+`.content` stops being one, so the whole page moves together — which is
+only available because this tracklist is plain DOM rather than a
+virtualizer, and because `.main-panel > *` already gives the host a
+definite height.
+
+Three things about it are load-bearing. **Another `min-width: 0` was
+not the fix**: `.album-info` carries one and was shrinking exactly as
+asked, to 112px beside a 200px cover — so the title drew as `G…` and
+"Shuffle album" ended at x=443 inside a 424px box, clipped by the
+component's own `overflow: hidden` and reachable by no gesture. A row
+with a fixed-size sibling has to **stack** at that width, or the column
+that must shrink has nothing to be wide with. **`layout-overflow.spec.ts`
+cannot see any of this** — `body.scrollWidth` equalled the viewport
+throughout, because the overflow was *inside* a component; the spec
+measures each header control against the host's own box, which is
+`top-bar-fit.spec.ts`'s shape for the same reason. And **the phone block
+is last in the stylesheet**, on `index.css`'s rule: a media query adds
+no specificity, so written above the plain rules it overrides every
+declaration in it is silently dead.
+
 **Activating a row plays the list the row is in, from that row.** A
 double-click — and Play on a single row's context menu — queues the
 list as *displayed* with `startIndex` on that row, not a queue of one
@@ -2997,6 +3587,25 @@ Pre-commit hooks verify generated code is fresh — always run `make generate` a
 Tests use `database.NewTestDB(t)` for in-memory SQLite, built by the same
 `applySchema` production uses so the two cannot diverge. Test audio fixtures live in `test_data/music_library_test/`. Table-driven tests are the norm.
 
+**`make ui-visual` is the one tier nothing but a person runs, and it
+cannot become one.** Its ten `toMatchScreenshot` baselines were recorded
+on a developer's Arch box; replayed in a bare `ubuntu:24.04` container
+— CI's `check` image — three of them fail on font metrics and
+compositing alone (`track-info` and one `page-header` shot at a 0.03
+mismatch ratio against a 0.02 allowance, `seek-bar` one pixel shorter),
+and two components disagree about their own height between the two
+machines. So CI keeps running `make ui-test`, which is the same suite
+with the comparisons off, and a pre-push hook would be the same fault
+with the machines swapped. What replaces the gate is a rule, in
+`.pi/skills/yellowjacket-dev/references/ui-tier.md`: **a change that
+moves a component's geometry refreshes that component's baseline in the
+same commit, having read the image, and never one it did not cause**.
+That is #196, which was four stale references accumulated across three
+unrelated merges — a red tier nobody could read, which is how it stayed
+red. A visual case must also **state the world it photographs**, since
+the stores are singletons and a case that sets nothing records whatever
+the previous one left in them.
+
 ## Git Workflow
 
 Feature branches and PRs are the only way in: **`main` is a protected
@@ -3264,6 +3873,27 @@ android-inspect` forwards the WebView's devtools socket and `make
 android-eval` asks the real page — raw CDP, because `connectOverCDP`
 calls `Browser.setDownloadBehavior` and a WebView refuses it.
 
+**One of those gaps is checked rather than remembered.** A nested rule
+whose selector starts with an element name is not a parse error anyone
+would notice on 113 — the rule simply does not exist, there and nowhere
+else, which is how the bottom bar's `text-overflow: ellipsis` came to
+have never truncated on the device. `make css-check`
+(`frontend/scripts/check-css-nesting.mjs`, a pre-commit hook and a CI
+step) fails on one, over every `frontend/*.css` and the `css` literals
+alike — a glob rather than `index.css` by name, because the hook fires
+on `frontend/**/*.{ts,css}` and a sweep that names one file goes green
+over a stylesheet it never opened — and
+says the fix is a leading `&` — valid in both syntaxes, so no nested
+rule here has a reason to omit it. Two things it has to get right, and
+both follow from asking whether a *style* rule is anywhere above rather
+than what the immediate parent is: `@media (…) { bottom-nav { … } }` at
+the top level is an ordinary rule and is the majority of what a regex
+over the file would report, while the same rule one level inside
+`.bar { @media (…) { … } }` is nested and is flagged. The check is the
+cheap version of the answer; a build-time downlevel (Lightning CSS
+targeting 113) would fix the class permanently and is a dependency and
+a build step rather than twenty lines.
+
 `build/config.yml`'s `version` is the
 *metadata* version and is not what the app reports — `main.version` is
 stamped at link time from the packaging recipe's git-derived version.

Makefile

@@ -160,8 +160,11 @@ ui-watch: ## Same suite, in watch mode
 ui-visual: ## Run the suite including screenshot comparisons
 	@cd frontend && YJ_VISUAL=1 npx vitest run $(UI_ARGS)
 
-ui-visual-update: ## Re-record the screenshot baselines
+# `--update=true`, never a bare `--update`: vitest takes the following
-	@cd frontend && YJ_VISUAL=1 npx vitest run --update $(UI_ARGS)
+# positional as the flag's value, so `--update <path>` swallows the path
+# and re-records every baseline in the repo instead of the one named.
+ui-visual-update: ## Re-record the screenshot baselines (UI_ARGS=<path> to filter)
+	@cd frontend && YJ_VISUAL=1 npx vitest run --update=true $(UI_ARGS)
 
 ui-setup: ## Install the Vitest browser provider's own Chromium (once)
 	@cd frontend && pnpm install && npx playwright install chromium
@@ -172,12 +175,17 @@ ui-setup: ## Install the Vitest browser provider's own Chromium (once)
 bindings-check: ## Fail if the generated bindings are stale
 	@./scripts/bindings-check.sh
 
+# Two CSS traps that report a long way from their cause, or not at all.
 # A backtick inside a comment in a css`` literal ends the literal, and
 # what you get back is a type error about CSSResult, or every test in
-# the suite failing to import. Four sessions, three plans. Instant.
+# the suite failing to import. Four sessions, three plans. And a nested
+# rule starting with an element name is dropped by the device's
+# Chrome 113 in silence -- no tier here runs an engine that can see it.
+# Instant.
 .PHONY: css-check
-css-check: ## Fail if a css`` literal was ended early by a backtick in a comment
+css-check: ## Fail on a css`` literal ended early by a backtick, or a nested rule needing an &
 	@cd frontend && node scripts/check-css-literals.mjs
+	@cd frontend && node scripts/check-css-nesting.mjs
 
 # .pi/ and CLAUDE.md document commands, and a doc that documents a
 # command wrongly is worse than no doc: an agent runs it confidently.

backend/androidlog/android.go

@@ -0,0 +1,55 @@
+//go:build android
+
+// The write itself, and nothing else. Everything decidable off a phone
+// is in androidlog.go; see the package comment for why.
+
+package androidlog
+
+/*
+#cgo LDFLAGS: -llog
+#include <stdlib.h>
+#include <android/log.h>
+*/
+import "C"
+
+import (
+	"log/slog"
+	"unsafe"
+)
+
+// The priorities in androidlog.go are android/log.h's own values, and
+// these are what says so. A constant expression that would be negative
+// does not compile as a uint, so a renumbered header fails the build
+// here rather than logging everything at the wrong severity -- which is
+// the failure that would otherwise be invisible, since logcat would
+// happily print whatever number it was handed.
+const (
+	_ = uint(C.ANDROID_LOG_VERBOSE - PrioVerbose)
+	_ = uint(PrioVerbose - C.ANDROID_LOG_VERBOSE)
+	_ = uint(C.ANDROID_LOG_DEBUG - PrioDebug)
+	_ = uint(PrioDebug - C.ANDROID_LOG_DEBUG)
+	_ = uint(C.ANDROID_LOG_INFO - PrioInfo)
+	_ = uint(PrioInfo - C.ANDROID_LOG_INFO)
+	_ = uint(C.ANDROID_LOG_WARN - PrioWarn)
+	_ = uint(PrioWarn - C.ANDROID_LOG_WARN)
+	_ = uint(C.ANDROID_LOG_ERROR - PrioError)
+	_ = uint(PrioError - C.ANDROID_LOG_ERROR)
+	_ = uint(C.ANDROID_LOG_FATAL - PrioFatal)
+	_ = uint(PrioFatal - C.ANDROID_LOG_FATAL)
+)
+
+// New returns the handler main() installs on Android.
+func New(opts *slog.HandlerOptions) slog.Handler {
+	return NewHandler(opts, write)
+}
+
+// write hands one line to liblog.
+func write(prio int, tag, msg string) {
+	cTag := C.CString(tag)
+	defer C.free(unsafe.Pointer(cTag))
+
+	cMsg := C.CString(msg)
+	defer C.free(unsafe.Pointer(cMsg))
+
+	C.__android_log_write(C.int(prio), cTag, cMsg)
+}

backend/androidlog/androidlog.go

@@ -0,0 +1,250 @@
+// Package androidlog routes slog to logcat.
+//
+// **An Android app's fd 1 and 2 go to /dev/null**, so every line this
+// app writes with slog is discarded on that platform -- including the
+// one naming the error it is about to os.Exit on. #52 is what that
+// cost: a process that vanished with no tombstone, no AndroidRuntime
+// stack and nothing in `logcat -b crash`, at Priority/Critical for
+// months, whose entire diagnosis was one slog.Error main.go was
+// already writing.
+//
+// The platform's own sink is __android_log_write, which is a handful
+// of cgo -- and cgo compiled by nothing `make lint` or `make test`
+// runs, since the only toolchain that builds the android tag is a
+// cross-compiler and the only thing that runs it is a phone. So the
+// split here is the one backend/mediacontrols/androidpayload.go makes,
+// pushed as far as it will go: **everything except the write itself is
+// in this file, untagged**. The priority mapping, the formatting, the
+// chunking and the handler's own attr and group bookkeeping are
+// ordinary Go that `go test` exercises on any platform; android.go is
+// fifteen lines that hand a string to liblog.
+package androidlog
+
+import (
+	"bytes"
+	"context"
+	"log/slog"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+// Tag is what logcat labels these lines with.
+//
+// It is a constant of ours rather than the application id, because the
+// debug build carries `applicationIdSuffix ".dev"` so that it can be
+// installed beside the release app -- so a tag derived from the package
+// name is a *different* tag on the one build that can be inspected, and
+// the filter that is supposed to show these lines would hide them on
+// exactly the build used to look for them.
+const Tag = "yellowjacket"
+
+// Android's priorities, from android/log.h. These are the values
+// __android_log_write takes; android.go asserts at compile time that
+// they still match the header, so a renumbered platform is a build
+// failure here rather than a warning silently logged as an error.
+const (
+	PrioVerbose = 2
+	PrioDebug   = 3
+	PrioInfo    = 4
+	PrioWarn    = 5
+	PrioError   = 6
+	PrioFatal   = 7
+)
+
+// maxPayload is how much of one line liblog will carry.
+//
+// The kernel logger's entry is 4068 bytes for the tag, the message and
+// their two NULs together, and what does not fit is **dropped without
+// comment** -- so a long line would be truncated in the middle of the
+// thing worth reading. 3500 leaves room for the tag and for the "(N/M)"
+// a continuation carries.
+const maxPayload = 3500
+
+// WriteFunc is the platform sink: one already-formatted line, at one
+// priority, under one tag.
+//
+// It is a parameter rather than a package-level function so that the
+// handler can be driven by a test on a machine with no liblog at all.
+type WriteFunc func(prio int, tag, msg string)
+
+// Priority maps a slog level onto an Android one.
+//
+// slog's levels are open -- a caller may define its own at any int --
+// so this is a banding rather than a lookup: anything below Info is
+// debug, anything at or above Error is error. A custom level between
+// two of the standard ones lands in the band beneath it, which is what
+// slog's own level naming does.
+func Priority(level slog.Level) int {
+	switch {
+	case level < slog.LevelDebug:
+		return PrioVerbose
+	case level < slog.LevelInfo:
+		return PrioDebug
+	case level < slog.LevelWarn:
+		return PrioInfo
+	case level < slog.LevelError:
+		return PrioWarn
+	default:
+		return PrioError
+	}
+}
+
+// Handler formats records with slog's own TextHandler and hands each
+// line to a WriteFunc.
+//
+// It delegates the formatting rather than doing it, because WithAttrs
+// and WithGroup are the half of slog.Handler that is easy to get subtly
+// wrong -- and a logger whose groups are wrong is a logger nobody reads.
+// What it does own is what logcat needs and TextHandler does not know
+// about: the priority, and the fact that a line has a maximum length.
+type Handler struct {
+	write WriteFunc
+
+	// mu guards buf, which the delegate writes into. slog.Handler is
+	// documented as safe for concurrent use.
+	mu       *sync.Mutex
+	buf      *bytes.Buffer
+	delegate slog.Handler
+}
+
+// NewHandler builds a handler over an arbitrary sink.
+//
+// The time and the level are dropped from the formatted line: logcat
+// stamps every entry with both, and repeating them costs a quarter of
+// the width of a phone-sized terminal to say the same thing twice.
+func NewHandler(opts *slog.HandlerOptions, write WriteFunc) *Handler {
+	buf := &bytes.Buffer{}
+
+	inner := &slog.HandlerOptions{}
+	if opts != nil {
+		*inner = *opts
+	}
+
+	user := inner.ReplaceAttr
+	inner.ReplaceAttr = func(groups []string, a slog.Attr) slog.Attr {
+		if len(groups) == 0 && isBuiltin(a) {
+			return slog.Attr{}
+		}
+
+		if user != nil {
+			return user(groups, a)
+		}
+
+		return a
+	}
+
+	return &Handler{
+		write:    write,
+		mu:       &sync.Mutex{},
+		buf:      buf,
+		delegate: slog.NewTextHandler(buf, inner),
+	}
+}
+
+// isBuiltin reports whether an attr is slog's own time or level,
+// rather than a caller's attribute that happens to share the name.
+//
+// ReplaceAttr cannot tell those apart by key. It is called with an
+// empty group path for the built-ins *and* for every top-level
+// attribute, so a key comparison alone silently eats a caller's own
+// "level" or "time" -- which is not hypothetical: the probe that
+// verified this package on the device logged one, and the attribute
+// vanished. The kinds are what separate them, because slog builds the
+// built-ins as slog.Any(LevelKey, r.Level) and slog.Time(TimeKey, ...)
+// and an attribute value of type slog.Level is not something a caller
+// passes by accident.
+func isBuiltin(a slog.Attr) bool {
+	switch a.Key {
+	case slog.TimeKey:
+		return a.Value.Kind() == slog.KindTime
+	case slog.LevelKey:
+		_, ok := a.Value.Any().(slog.Level)
+
+		return ok
+	default:
+		return false
+	}
+}
+
+// Enabled reports whether the level is worth formatting.
+func (h *Handler) Enabled(ctx context.Context, level slog.Level) bool {
+	return h.delegate.Enabled(ctx, level)
+}
+
+// Handle formats one record and writes it out, in as many entries as
+// its length demands.
+func (h *Handler) Handle(ctx context.Context, rec slog.Record) error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
+	h.buf.Reset()
+
+	if err := h.delegate.Handle(ctx, rec); err != nil {
+		return err
+	}
+
+	prio := Priority(rec.Level)
+	for _, line := range Chunk(strings.TrimRight(h.buf.String(), "\n")) {
+		h.write(prio, Tag, line)
+	}
+
+	return nil
+}
+
+// WithAttrs returns a handler carrying the given attributes.
+func (h *Handler) WithAttrs(attrs []slog.Attr) slog.Handler {
+	return h.derive(h.delegate.WithAttrs(attrs))
+}
+
+// WithGroup returns a handler that qualifies subsequent attributes.
+func (h *Handler) WithGroup(name string) slog.Handler {
+	return h.derive(h.delegate.WithGroup(name))
+}
+
+// derive shares the buffer and its mutex with the parent.
+//
+// They must be shared rather than copied: the delegate returned by
+// WithAttrs writes into the *same* buffer this one does, so a second
+// mutex would guard nothing and two loggers derived from one would
+// interleave their bytes into a single line.
+func (h *Handler) derive(delegate slog.Handler) *Handler {
+	return &Handler{
+		write:    h.write,
+		mu:       h.mu,
+		buf:      h.buf,
+		delegate: delegate,
+	}
+}
+
+// Chunk splits a formatted record into entries liblog will carry
+// whole.
+//
+// A record short enough to fit is returned as it is, which is nearly
+// every record; the numbering only appears where something was going
+// to be silently truncated anyway. It splits on bytes rather than runes
+// because the limit is a byte count -- a multi-byte rune straddling the
+// boundary is a mojibake character in a log line, against a lost one.
+func Chunk(msg string) []string {
+	if len(msg) <= maxPayload {
+		return []string{msg}
+	}
+
+	var parts []string
+
+	for rest := msg; rest != ""; {
+		n := min(maxPayload, len(rest))
+		parts = append(parts, rest[:n])
+		rest = rest[n:]
+	}
+
+	numbered := make([]string, 0, len(parts))
+	for i, p := range parts {
+		numbered = append(
+			numbered,
+			"("+strconv.Itoa(i+1)+"/"+strconv.Itoa(len(parts))+") "+p,
+		)
+	}
+
+	return numbered
+}

backend/androidlog/androidlog_test.go

@@ -0,0 +1,355 @@
+package androidlog_test
+
+import (
+	"log/slog"
+	"strings"
+	"sync"
+	"testing"
+
+	"yellowjacket/backend/androidlog"
+)
+
+// entry is one call to the sink.
+type entry struct {
+	prio int
+	tag  string
+	msg  string
+}
+
+// recorder is the platform write, on a machine with no platform.
+type recorder struct {
+	mu      sync.Mutex
+	entries []entry
+}
+
+func (r *recorder) write(prio int, tag, msg string) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	r.entries = append(r.entries, entry{prio: prio, tag: tag, msg: msg})
+}
+
+func (r *recorder) only(t *testing.T) entry {
+	t.Helper()
+
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	if len(r.entries) != 1 {
+		t.Fatalf("want exactly one entry, got %d: %v", len(r.entries), r.entries)
+	}
+
+	return r.entries[0]
+}
+
+func newLogger(r *recorder, level slog.Level) *slog.Logger {
+	return slog.New(androidlog.NewHandler(
+		&slog.HandlerOptions{Level: level},
+		r.write,
+	))
+}
+
+// TestPriorityMapsEveryLevel pins the level banding.
+//
+// This is the one thing in #160 that a wrong answer hides rather than
+// breaks: logcat prints whatever priority it is handed, so an Error
+// filed as Info is a line that is present, correct and invisible to
+// every filter anyone would use to look for it.
+func TestPriorityMapsEveryLevel(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name  string
+		level slog.Level
+		want  int
+	}{
+		{"below debug is verbose", slog.LevelDebug - 1, androidlog.PrioVerbose},
+		{"debug", slog.LevelDebug, androidlog.PrioDebug},
+		{"info", slog.LevelInfo, androidlog.PrioInfo},
+		{"warn", slog.LevelWarn, androidlog.PrioWarn},
+		{"error", slog.LevelError, androidlog.PrioError},
+
+		// slog's levels are open, so a caller may sit between two of
+		// the named ones.  Each lands in the band beneath it, which is
+		// what slog's own level naming does ("INFO+2").
+		{"between info and warn", slog.LevelInfo + 2, androidlog.PrioInfo},
+		{"between warn and error", slog.LevelWarn + 1, androidlog.PrioWarn},
+		{"above error", slog.LevelError + 4, androidlog.PrioError},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			if got := androidlog.Priority(tt.level); got != tt.want {
+				t.Errorf("Priority(%v) = %d, want %d", tt.level, got, tt.want)
+			}
+		})
+	}
+}
+
+// TestPrioritiesAreTheHeadersValues pins the constants themselves.
+//
+// android.go asserts these against android/log.h at compile time, but
+// only a cross-compiler ever builds that file.  This is the assertion
+// that runs in CI, and the numbers are written out longhand on purpose
+// -- comparing a constant to itself would pass on any renumbering.
+func TestPrioritiesAreTheHeadersValues(t *testing.T) {
+	t.Parallel()
+
+	for _, tt := range []struct {
+		name string
+		got  int
+		want int
+	}{
+		{"verbose", androidlog.PrioVerbose, 2},
+		{"debug", androidlog.PrioDebug, 3},
+		{"info", androidlog.PrioInfo, 4},
+		{"warn", androidlog.PrioWarn, 5},
+		{"error", androidlog.PrioError, 6},
+		{"fatal", androidlog.PrioFatal, 7},
+	} {
+		if tt.got != tt.want {
+			t.Errorf("%s priority = %d, want %d", tt.name, tt.got, tt.want)
+		}
+	}
+}
+
+// TestRecordReachesTheSink is the whole point of the package: a line
+// written with slog arrives, under the app's tag, at the right
+// priority.
+func TestRecordReachesTheSink(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	newLogger(rec, slog.LevelInfo).Error("application error", "err", "boom")
+
+	got := rec.only(t)
+
+	if got.prio != androidlog.PrioError {
+		t.Errorf("priority = %d, want %d", got.prio, androidlog.PrioError)
+	}
+
+	if got.tag != androidlog.Tag {
+		t.Errorf("tag = %q, want %q", got.tag, androidlog.Tag)
+	}
+
+	if !strings.Contains(got.msg, "application error") {
+		t.Errorf("message %q does not carry the message", got.msg)
+	}
+
+	if !strings.Contains(got.msg, `err=boom`) {
+		t.Errorf("message %q does not carry the attribute", got.msg)
+	}
+}
+
+// TestTheTagIsNotTheApplicationID guards the trap the tag exists to
+// avoid.
+//
+// The debug build carries `applicationIdSuffix ".dev"`, so it is
+// installed as app.yellowjacket.dev -- and it is the *only* build whose
+// WebView can be inspected, so it is the build anyone debugging this
+// app is running.  A tag derived from the application id therefore
+// differs between the build being looked at and the build the filter
+// was written for, which is the failure this whole issue is about
+// wearing a different hat.
+func TestTheTagIsNotTheApplicationID(t *testing.T) {
+	t.Parallel()
+
+	if strings.Contains(androidlog.Tag, ".") {
+		t.Errorf(
+			"tag %q looks like an application id; it must be stable "+
+				"across the debug suffix",
+			androidlog.Tag,
+		)
+	}
+
+	// Logcat's tag field is 23 bytes.  A longer one is truncated, and a
+	// truncated tag matches no filter.
+	if len(androidlog.Tag) > 23 {
+		t.Errorf("tag %q is %d bytes, over logcat's 23", androidlog.Tag, len(androidlog.Tag))
+	}
+}
+
+// TestTimeAndLevelAreDropped checks the formatting decision.
+//
+// logcat stamps every entry with a timestamp and a priority letter, so
+// carrying slog's own is the same information twice on a 424px screen.
+func TestTimeAndLevelAreDropped(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	newLogger(rec, slog.LevelInfo).Warn("scan finished", "files", 1577)
+
+	got := rec.only(t).msg
+
+	if strings.Contains(got, "time=") {
+		t.Errorf("message %q still carries a timestamp", got)
+	}
+
+	if strings.Contains(got, "level=") {
+		t.Errorf("message %q still carries a level", got)
+	}
+
+	if !strings.Contains(got, "files=1577") {
+		t.Errorf("message %q lost its attributes with them", got)
+	}
+}
+
+// TestACallersOwnLevelAttrSurvives is a regression, and it was found on
+// the phone rather than here.
+//
+// Dropping slog's built-in time and level by key alone also drops a
+// caller's attribute of the same name, because ReplaceAttr sees an
+// empty group path for both. The probe that verified this package on
+// the device wrote slog.Info("...", "level", "info") and logcat showed
+// the message with no attributes at all.
+func TestACallersOwnLevelAttrSurvives(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	newLogger(rec, slog.LevelInfo).Info("probe", "level", "info", "time", "soon")
+
+	got := rec.only(t).msg
+
+	for _, want := range []string{"level=info", "time=soon"} {
+		if !strings.Contains(got, want) {
+			t.Errorf("message %q lost the caller's %q", got, want)
+		}
+	}
+
+	// And slog's own are still gone: the built-in level renders as a
+	// bare word like INFO, never as the caller's value.
+	if strings.Contains(got, "level=INFO") {
+		t.Errorf("message %q carries slog's own level", got)
+	}
+}
+
+// TestLevelIsHonoured checks that Enabled reaches the delegate.
+func TestLevelIsHonoured(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	log := newLogger(rec, slog.LevelWarn)
+
+	log.Info("not this one")
+	log.Warn("this one")
+
+	if got := rec.only(t).msg; !strings.Contains(got, "this one") {
+		t.Errorf("wrong record survived: %q", got)
+	}
+}
+
+// TestGroupsAndAttrsSurvive covers the half of slog.Handler this
+// delegates rather than implements -- the reason it delegates at all.
+func TestGroupsAndAttrsSurvive(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	log := newLogger(rec, slog.LevelInfo).
+		With("component", "player").
+		WithGroup("track")
+
+	log.Info("loaded", "path", "/sdcard/Music/a.flac")
+
+	got := rec.only(t).msg
+
+	for _, want := range []string{
+		"component=player",
+		"track.path=/sdcard/Music/a.flac",
+	} {
+		if !strings.Contains(got, want) {
+			t.Errorf("message %q is missing %q", got, want)
+		}
+	}
+}
+
+// TestDerivedHandlersDoNotInterleave is why derive shares the buffer's
+// mutex rather than taking a new one.
+//
+// Two loggers derived from one write into the same buffer, so a second
+// mutex would guard nothing and a concurrent pair would splice each
+// other's bytes into a single line -- which reads as corrupted logs
+// under load and as nothing at all in a test that logs once.
+func TestDerivedHandlersDoNotInterleave(t *testing.T) {
+	t.Parallel()
+
+	rec := &recorder{}
+	base := newLogger(rec, slog.LevelInfo)
+
+	var wg sync.WaitGroup
+
+	for i := range 8 {
+		wg.Add(1)
+
+		go func() {
+			defer wg.Done()
+
+			log := base.With("worker", i).WithGroup("g")
+			for range 50 {
+				log.Info("tick", "n", i)
+			}
+		}()
+	}
+
+	wg.Wait()
+
+	rec.mu.Lock()
+	defer rec.mu.Unlock()
+
+	if len(rec.entries) != 8*50 {
+		t.Fatalf("got %d entries, want %d", len(rec.entries), 8*50)
+	}
+
+	for _, e := range rec.entries {
+		if strings.Count(e.msg, "msg=tick") != 1 {
+			t.Fatalf("interleaved line: %q", e.msg)
+		}
+	}
+}
+
+// TestChunkLeavesShortLinesAlone is the common case: no numbering
+// appears on a record that was never going to be truncated.
+func TestChunkLeavesShortLinesAlone(t *testing.T) {
+	t.Parallel()
+
+	got := androidlog.Chunk("msg=short")
+
+	if len(got) != 1 || got[0] != "msg=short" {
+		t.Errorf("Chunk(short) = %q, want the input unchanged", got)
+	}
+}
+
+// TestChunkSplitsWhatWouldBeTruncated covers the case liblog drops
+// silently.
+func TestChunkSplitsWhatWouldBeTruncated(t *testing.T) {
+	t.Parallel()
+
+	const n = 9000
+
+	long := strings.Repeat("x", n)
+	parts := androidlog.Chunk(long)
+
+	if len(parts) < 2 {
+		t.Fatalf("a %d-byte line was not split", n)
+	}
+
+	var payload strings.Builder
+
+	for i, p := range parts {
+		if len(p) > 4000 {
+			t.Errorf("part %d is %d bytes, over liblog's entry", i, len(p))
+		}
+
+		_, rest, found := strings.Cut(p, ") ")
+		if !found {
+			t.Fatalf("part %d carries no (n/m) marker: %q", i, p)
+		}
+
+		payload.WriteString(rest)
+	}
+
+	if payload.String() != long {
+		t.Errorf("the parts do not reassemble into the input")
+	}
+}

backend/database/sql/queries/albums.sql

@@ -40,7 +40,8 @@ WHERE id = ? AND (mbid IS NULL OR mbid = '');
 -- name: GetAlbumsWithPendingReleaseMBID :many
 SELECT id, pending_release_mbid FROM albums
 WHERE pending_release_mbid IS NOT NULL AND pending_release_mbid != ''
-  AND (mbid IS NULL OR mbid = '');
+  AND (mbid IS NULL OR mbid = '')
+LIMIT ?;
 
 -- name: DeleteAlbum :exec
 DELETE FROM albums WHERE id = ?;

backend/database/sql/sqlcgen/albums.sql.go

@@ -331,6 +331,7 @@ const getAlbumsWithPendingReleaseMBID = `-- name: GetAlbumsWithPendingReleaseMBI
 SELECT id, pending_release_mbid FROM albums
 WHERE pending_release_mbid IS NOT NULL AND pending_release_mbid != ''
   AND (mbid IS NULL OR mbid = '')
+LIMIT ?
 `
 
 type GetAlbumsWithPendingReleaseMBIDRow struct {
@@ -338,8 +339,8 @@ type GetAlbumsWithPendingReleaseMBIDRow struct {
 	PendingReleaseMbid sql.NullString
 }
 
-func (q *Queries) GetAlbumsWithPendingReleaseMBID(ctx context.Context) ([]GetAlbumsWithPendingReleaseMBIDRow, error) {
+func (q *Queries) GetAlbumsWithPendingReleaseMBID(ctx context.Context, limit int64) ([]GetAlbumsWithPendingReleaseMBIDRow, error) {
-	rows, err := q.db.QueryContext(ctx, getAlbumsWithPendingReleaseMBID)
+	rows, err := q.db.QueryContext(ctx, getAlbumsWithPendingReleaseMBID, limit)
 	if err != nil {
 		return nil, err
 	}

backend/explore/explore.go

@@ -2,6 +2,7 @@ package explore
 
 import (
 	"context"
+	"database/sql"
 	"log/slog"
 	"math"
 	"sort"
@@ -12,6 +13,7 @@ import (
 	"golang.org/x/sync/singleflight"
 
 	"yellowjacket/backend/database"
+	"yellowjacket/backend/database/sql/sqlcgen"
 	"yellowjacket/backend/events"
 	"yellowjacket/backend/jobs"
 )
@@ -279,37 +281,32 @@ func (e *Service) BackfillReleaseGroupMBIDs() {
 	go e.backfillReleaseGroupMBIDs(e.ctx)
 }
 
-func (e *Service) backfillReleaseGroupMBIDs(ctx context.Context) {
+// pendingReleaseMBIDs is the albums this pass has work to do on.
-	rows, err := e.db.QueryContext(
+//
-		"SELECT id, pending_release_mbid FROM release_groups "+
+// It is separate from the pass, and returns its error rather than
-			"WHERE (mbid IS NULL OR mbid = '') "+
+// logging it, so that a test can assert the statement runs against the
-			"AND pending_release_mbid IS NOT NULL AND pending_release_mbid != '' "+
+// real schema. That is not a general preference -- it is this
-			"LIMIT ?",
+// statement's history: it named `release_groups`, a table plan 013
-		releaseGroupMBIDBackfillMaxPerRun,
+// renamed to `albums`, so it failed on every launch since e7748f1 and
+// the pass returned quietly having done nothing. A test of the pass
+// as a whole cannot see that, because a query error and an empty
+// library are the same early return.
+func (e *Service) pendingReleaseMBIDs(
+	ctx context.Context,
+) ([]sqlcgen.GetAlbumsWithPendingReleaseMBIDRow, error) {
+	return e.db.ReadQueries.GetAlbumsWithPendingReleaseMBID(
+		ctx, releaseGroupMBIDBackfillMaxPerRun,
 	)
+}
+
+func (e *Service) backfillReleaseGroupMBIDs(ctx context.Context) {
+	pending, err := e.pendingReleaseMBIDs(ctx)
 	if err != nil {
 		e.logger.Warn("release-group mbid backfill: query failed", "error", err)
 
 		return
 	}
 
-	type pendingRow struct {
-		id          int64
-		releaseMBID string
-	}
-
-	var pending []pendingRow
-
-	for rows.Next() {
-		var p pendingRow
-
-		if err := rows.Scan(&p.id, &p.releaseMBID); err == nil {
-			pending = append(pending, p)
-		}
-	}
-
-	_ = rows.Close()
-
 	if len(pending) == 0 {
 		return
 	}
@@ -335,7 +332,7 @@ func (e *Service) backfillReleaseGroupMBIDs(ctx context.Context) {
 
 		job.progress(i, len(pending))
 
-		release, err := e.mb.LookupRelease(ctx, p.releaseMBID)
+		release, err := e.mb.LookupRelease(ctx, p.PendingReleaseMbid.String)
 		if err != nil || release.ReleaseGroupMBID == "" {
 			// Left alone rather than cleared: LookupRelease caches its
 			// answer (success or a release with no group) for 7 days,
@@ -344,12 +341,19 @@ func (e *Service) backfillReleaseGroupMBIDs(ctx context.Context) {
 			continue
 		}
 
-		_, err = e.db.ExecContext(
+		// The writer, not ReadQueries: an UPDATE issued on the
-			"UPDATE release_groups SET mbid = ?, pending_release_mbid = NULL "+
+		// query-only pool fails at runtime with "attempt to write a
-				"WHERE id = ? AND (mbid IS NULL OR mbid = '')",
+		// readonly database".
-			release.ReleaseGroupMBID, p.id,
+		if err := e.db.Queries.ResolveAlbumPendingReleaseMBID(
-		)
+			ctx,
-		if err != nil {
+			sqlcgen.ResolveAlbumPendingReleaseMBIDParams{
+				Mbid: sql.NullString{
+					String: release.ReleaseGroupMBID,
+					Valid:  true,
+				},
+				ID: p.ID,
+			},
+		); err != nil {
 			e.logger.Warn("release-group mbid backfill: update failed", "error", err)
 		}
 	}

backend/explore/pendingreleasembid_test.go

@@ -0,0 +1,250 @@
+package explore
+
+import (
+	"database/sql"
+	"log/slog"
+	"strconv"
+	"testing"
+
+	"yellowjacket/backend/database"
+	"yellowjacket/backend/database/sql/sqlcgen"
+)
+
+// The release-group MBID backfill queried `release_groups`, a table
+// plan 013 renamed to `albums`, so it failed on its first statement on
+// every launch from e7748f1 until #189 -- and the pass swallowed that,
+// because a query error and an empty library are the same early
+// return. Nothing noticed for two reasons worth keeping in mind:
+//
+//   - the statement was **raw SQL**, so sqlc never read it. Every other
+//     statement in the repo was renamed by the same change because sqlc
+//     reads sql/schemas/ and cannot generate against a table that is not
+//     declared. The two sqlc queries this now calls were written by 013
+//     and left uncalled.
+//   - it needs no network and no fixture library to reproduce. The
+//     failure is at prepare time.
+
+// seedPendingAlbum inserts an album whose files carried a release MBID
+// but no release-group MBID, which is what `library.updateMBIDs`
+// leaves behind for this pass to resolve.
+func seedPendingAlbum(
+	t *testing.T,
+	db *database.DB,
+	name, pendingMBID string,
+) int64 {
+	t.Helper()
+
+	res, err := db.ExecContext(
+		"INSERT INTO albums (name, artist_credit, pending_release_mbid) "+
+			"VALUES (?, ?, ?)",
+		name, "Test Artist", pendingMBID,
+	)
+	if err != nil {
+		t.Fatalf("insert albums row: %v", err)
+	}
+
+	id, err := res.LastInsertId()
+	if err != nil {
+		t.Fatalf("last insert id: %v", err)
+	}
+
+	return id
+}
+
+func newPendingTestService(db *database.DB) *Service {
+	return &Service{db: db, logger: slog.Default()}
+}
+
+// TestPendingReleaseMBIDsRunsAgainstTheRealSchema is the regression.
+//
+// It asserts the statement *runs*, which is the whole of what was
+// broken: against the old raw SQL this returns
+// "no such table: release_groups" rather than a row.
+func TestPendingReleaseMBIDsRunsAgainstTheRealSchema(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+	e := newPendingTestService(db)
+
+	want := seedPendingAlbum(t, db, "Pending Album", "release-mbid-1")
+
+	pending, err := e.pendingReleaseMBIDs(db.Ctx)
+	if err != nil {
+		t.Fatalf("the backfill's query failed: %v", err)
+	}
+
+	if len(pending) != 1 {
+		t.Fatalf("got %d pending albums, want 1", len(pending))
+	}
+
+	if pending[0].ID != want {
+		t.Errorf("got album id %d, want %d", pending[0].ID, want)
+	}
+
+	if got := pending[0].PendingReleaseMbid.String; got != "release-mbid-1" {
+		t.Errorf("got pending mbid %q, want %q", got, "release-mbid-1")
+	}
+}
+
+// TestOnlyUnresolvedAlbumsAreReturned pins the two conditions that make
+// the pass idempotent, since between them they are what stops it doing
+// the same MusicBrainz lookups on every launch forever.
+func TestOnlyUnresolvedAlbumsAreReturned(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+	e := newPendingTestService(db)
+
+	pendingID := seedPendingAlbum(t, db, "Still Pending", "release-mbid-1")
+
+	// Already resolved: it has a real MBID, so there is nothing to
+	// look up even though a marker is still sitting on it.
+	resolved := seedPendingAlbum(t, db, "Already Resolved", "release-mbid-2")
+	if err := db.Queries.SetAlbumMBID(db.Ctx, sqlcgen.SetAlbumMBIDParams{
+		Mbid: sql.NullString{String: "rg-mbid", Valid: true},
+		ID:   resolved,
+	}); err != nil {
+		t.Fatalf("set album mbid: %v", err)
+	}
+
+	// Never had a release MBID to resolve in the first place, which is
+	// most of a library.
+	seedPendingAlbum(t, db, "Nothing Pending", "")
+
+	pending, err := e.pendingReleaseMBIDs(db.Ctx)
+	if err != nil {
+		t.Fatalf("the backfill's query failed: %v", err)
+	}
+
+	if len(pending) != 1 || pending[0].ID != pendingID {
+		t.Fatalf(
+			"got %d albums %v, want only the unresolved one (%d)",
+			len(pending), pending, pendingID,
+		)
+	}
+}
+
+// TestResolvingClearsTheMarker is the other half: once the lookup has
+// answered, the album must stop being a candidate, or the pass repeats
+// the same live MusicBrainz call on every launch.
+func TestResolvingClearsTheMarker(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+	e := newPendingTestService(db)
+
+	id := seedPendingAlbum(t, db, "Pending Album", "release-mbid-1")
+
+	// The writer, deliberately: this is an UPDATE, and the read pool
+	// would refuse it at runtime.
+	if err := db.Queries.ResolveAlbumPendingReleaseMBID(
+		db.Ctx,
+		sqlcgen.ResolveAlbumPendingReleaseMBIDParams{
+			Mbid: sql.NullString{String: "resolved-rg-mbid", Valid: true},
+			ID:   id,
+		},
+	); err != nil {
+		t.Fatalf("resolve pending release mbid: %v", err)
+	}
+
+	pending, err := e.pendingReleaseMBIDs(db.Ctx)
+	if err != nil {
+		t.Fatalf("the backfill's query failed: %v", err)
+	}
+
+	if len(pending) != 0 {
+		t.Fatalf("a resolved album is still a candidate: %v", pending)
+	}
+
+	album, err := db.ReadQueries.GetAlbum(db.Ctx, id)
+	if err != nil {
+		t.Fatalf("get album: %v", err)
+	}
+
+	if album.Mbid.String != "resolved-rg-mbid" {
+		t.Errorf("album mbid = %q, want the resolved one", album.Mbid.String)
+	}
+
+	if album.PendingReleaseMbid.Valid &&
+		album.PendingReleaseMbid.String != "" {
+		t.Errorf(
+			"the pending marker survived as %q",
+			album.PendingReleaseMbid.String,
+		)
+	}
+}
+
+// TestAResolvedMBIDIsNeverOverwritten covers the guard in the UPDATE.
+//
+// The pass runs against rows it read earlier, and a rescan can resolve
+// an album from its tags in between -- a real MBID from the file must
+// win over one this pass inferred from a release.
+func TestAResolvedMBIDIsNeverOverwritten(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+
+	id := seedPendingAlbum(t, db, "Pending Album", "release-mbid-1")
+
+	if err := db.Queries.SetAlbumMBID(db.Ctx, sqlcgen.SetAlbumMBIDParams{
+		Mbid: sql.NullString{String: "from-the-tags", Valid: true},
+		ID:   id,
+	}); err != nil {
+		t.Fatalf("set album mbid: %v", err)
+	}
+
+	if err := db.Queries.ResolveAlbumPendingReleaseMBID(
+		db.Ctx,
+		sqlcgen.ResolveAlbumPendingReleaseMBIDParams{
+			Mbid: sql.NullString{String: "from-the-backfill", Valid: true},
+			ID:   id,
+		},
+	); err != nil {
+		t.Fatalf("resolve pending release mbid: %v", err)
+	}
+
+	album, err := db.ReadQueries.GetAlbum(db.Ctx, id)
+	if err != nil {
+		t.Fatalf("get album: %v", err)
+	}
+
+	if album.Mbid.String != "from-the-tags" {
+		t.Errorf(
+			"album mbid = %q, want the tagged one to have won",
+			album.Mbid.String,
+		)
+	}
+}
+
+// TestThePassIsBounded checks the LIMIT.
+//
+// Each row costs a live MusicBrainz lookup on a 1 req/s limiter shared
+// with every page the user can open, so an unbounded read is a run that
+// lasts as long as the library is untagged. The sqlc query 013 wrote
+// had no LIMIT; the raw statement it was replacing did.
+func TestThePassIsBounded(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+	e := newPendingTestService(db)
+
+	for i := range releaseGroupMBIDBackfillMaxPerRun + 10 {
+		seedPendingAlbum(
+			t, db,
+			"Album "+string(rune('A'+i%26))+strconv.Itoa(i),
+			"release-mbid-"+strconv.Itoa(i),
+		)
+	}
+
+	pending, err := e.pendingReleaseMBIDs(db.Ctx)
+	if err != nil {
+		t.Fatalf("the backfill's query failed: %v", err)
+	}
+
+	if len(pending) != releaseGroupMBIDBackfillMaxPerRun {
+		t.Errorf(
+			"got %d albums, want the run bounded at %d",
+			len(pending), releaseGroupMBIDBackfillMaxPerRun,
+		)
+	}
+}

backend/metadata/tags.go

@@ -74,6 +74,14 @@ func ExtractTags(path string) (*TrackMetadata, error) {
 
 // ExtractTagsFromReader reads metadata from an io.ReadSeeker.
 func ExtractTagsFromReader(r io.ReadSeeker) (*TrackMetadata, error) {
+	// The container decides, so this is asked before tag.ReadFrom and
+	// not after its failure: a WAV's tags live in a RIFF chunk that
+	// dhowden/tag cannot see, and its fallback -- an ID3v1 trailer --
+	// would otherwise outrank them.
+	if meta, ok := wavTags(r); ok {
+		return meta, nil
+	}
+
 	m, err := tag.ReadFrom(r)
 	if err != nil {
 		// No tags found is not necessarily an error - return empty metadata

backend/metadata/tags_wav.go

@@ -0,0 +1,68 @@
+package metadata
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+
+	"yellowjacket/backend/riff"
+)
+
+// wavTags reads the ID3v2 tag a WAV carries in its RIFF "id3 " chunk,
+// which is where backend/tagwriter puts it and where dhowden/tag --
+// having no RIFF reader at all -- cannot look.  Without this a WAV
+// scans as an untagged file however carefully it was tagged.
+//
+// ok is false when r is not a RIFF/WAVE container, and the read
+// position is restored either way so the caller can carry on.
+func wavTags(r io.ReadSeeker) (*TrackMetadata, bool) {
+	start, err := r.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return nil, false
+	}
+
+	id3Data, chunkErr := riff.ID3Chunk(r)
+
+	if _, err := r.Seek(start, io.SeekStart); err != nil {
+		return nil, false
+	}
+
+	switch {
+	case chunkErr == nil:
+		return wavTagsFrom(id3Data), true
+
+	// Not ours to read: let the ordinary dispatch have the file.
+	case errors.Is(chunkErr, riff.ErrNotRIFF), errors.Is(chunkErr, riff.ErrNotWAVE):
+		return nil, false
+
+	// A RIFF container we cannot get a tag out of -- no chunk, an RF64
+	// file, a truncated header.  That is a file with no readable tags,
+	// which is what the scanner's filename fallback is for.
+	default:
+		return &TrackMetadata{}, true
+	}
+}
+
+// wavTagsFrom parses the bytes of a WAV's ID3v2 chunk.
+func wavTagsFrom(id3Data []byte) *TrackMetadata {
+	meta, err := extractID3v2Lenient(bytes.NewReader(id3Data))
+	if err != nil {
+		// A tag holding no frames is not a damaged tag: writing every
+		// field back out empty leaves one, and warning about it would
+		// put a fault on a file that has none.
+		if errors.Is(err, ErrTagsUnreadable) {
+			return &TrackMetadata{}
+		}
+
+		return &TrackMetadata{
+			TagReadWarning: fmt.Errorf("%w: %w", ErrTagsUnreadable, err),
+		}
+	}
+
+	// extractID3v2Lenient names MP3, being the recovery path for one.
+	meta.FileFormat = strings.ToUpper(strings.TrimPrefix(string(WAV), "."))
+
+	return meta
+}

backend/player/buffered_streamer.go

@@ -47,6 +47,39 @@ type BufferedStreamer struct {
 	// seek bar and suppresses its interpolation.
 	starved      int
 	starvedSince time.Time
+
+	// underruns accumulates for the life of this streamer, where
+	// starved is reset by every arriving sample.
+	//
+	// The two answer different questions and only the first was being
+	// asked. starved is a *stall* detector: it exists to end a track
+	// whose source has died, so it forgets a run the moment audio
+	// resumes -- which is exactly the case this counts. A hundred 20ms
+	// underruns a minute never approach the give-up threshold and were
+	// invisible to the log, the UI and every test tier, while being
+	// audible as static: an underrun is served as a run of zeros
+	// spliced into the waveform, and a step discontinuity at each edge
+	// is what a click is.
+	underruns UnderrunStats
+}
+
+// UnderrunStats is what the ring buffer missed, cumulatively.
+//
+// Samples rather than milliseconds because this type does not know the
+// sample rate -- the player does, and converts at the point of
+// reporting.
+type UnderrunStats struct {
+	// Runs is the number of *episodes*: transitions from healthy into
+	// starved. Calls is how many Stream calls were served with
+	// silence, and Samples is how much silence that was.
+	//
+	// Runs is the count that means something audible. One episode is
+	// one pop however many calls it spans, and the ratio of the two is
+	// how long the average episode was -- which is what separates
+	// "clicking" from "dropping out".
+	Runs    int64
+	Calls   int64
+	Samples int64
 }
 
 // The silence fill is bounded by both a duration and a run of calls,
@@ -226,6 +259,13 @@ func (bs *BufferedStreamer) Stream(
 		// but only for a bounded stretch, because "forever" is
 		// reported upward as healthy playback and there is no watchdog
 		// above this to notice otherwise.
+		if bs.starved == 0 {
+			bs.underruns.Runs++
+		}
+
+		bs.underruns.Calls++
+		bs.underruns.Samples += int64(len(samples))
+
 		bs.starved++
 
 		if bs.starvedSince.IsZero() {
@@ -269,6 +309,20 @@ func (bs *BufferedStreamer) Stream(
 	return n, true
 }
 
+// Underruns returns the cumulative underrun count.
+//
+// It is a snapshot rather than a live view, and it is read from
+// outside the audio callback: counting happens in Stream, under the
+// lock it already takes, because that path has a real-time deadline
+// and anything that allocates or formats on it is a cause of the
+// defect it is measuring rather than a measurement of it.
+func (bs *BufferedStreamer) Underruns() UnderrunStats {
+	bs.mu.Lock()
+	defer bs.mu.Unlock()
+
+	return bs.underruns
+}
+
 // Err returns any error encountered by the source streamer.
 func (bs *BufferedStreamer) Err() error {
 	bs.mu.Lock()
@@ -298,6 +352,10 @@ func (bs *BufferedStreamer) Flush() {
 
 // resetStarvationLocked forgets an underrun run.  Must be called with
 // bs.mu held.
+//
+// Deliberately does not touch bs.underruns: forgetting the run is what
+// makes starved a stall detector, and remembering it is the whole
+// point of the counter beside it.
 func (bs *BufferedStreamer) resetStarvationLocked() {
 	bs.starved = 0
 	bs.starvedSince = time.Time{}

backend/player/buffered_underrun_test.go

@@ -0,0 +1,279 @@
+package player
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+// An underrun is audible and nothing counted it (#135).
+//
+// The distinction these tests exist for is that `starved` and
+// `underruns` disagree on purpose. `starved` is a stall detector: it is
+// reset by every arriving sample, because its job is to end a track
+// whose source has died and a source that is merely slow must not be
+// cut short (TestUnderrunsDoNotAccumulateAcrossASlowSource, next
+// door). That reset is exactly what made the audible case invisible --
+// a hundred short underruns a minute never approach the give-up
+// threshold, and each one is a run of zeros spliced into the waveform
+// with a step discontinuity at both edges.
+
+// TestAnEmptyRingIsCounted is the measurement itself: silence served
+// for a missing sample is recorded rather than merely tolerated.
+func TestAnEmptyRingIsCounted(t *testing.T) {
+	t.Parallel()
+
+	// A source that never produces is the cleanest way to make the
+	// ring empty on demand; the stall budget is far longer than the
+	// handful of calls below.
+	bs := NewBufferedStreamer(stalledStreamer{}, 1024)
+	defer bs.Close()
+
+	if got := bs.Underruns(); got != (UnderrunStats{}) {
+		t.Fatalf("a fresh streamer already reports %+v", got)
+	}
+
+	buf := make([][2]float64, 256)
+
+	for range 3 {
+		if _, ok := bs.Stream(buf); !ok {
+			t.Fatal("the stall budget ran out before the test did")
+		}
+	}
+
+	got := bs.Underruns()
+
+	if got.Calls != 3 {
+		t.Errorf("Calls = %d, want 3", got.Calls)
+	}
+
+	if got.Samples != int64(3*len(buf)) {
+		t.Errorf("Samples = %d, want %d", got.Samples, 3*len(buf))
+	}
+
+	// Three consecutive silent calls are one episode, not three. That
+	// is the number that means something audible: one interruption is
+	// one pop however many callbacks it spans.
+	if got.Runs != 1 {
+		t.Errorf("Runs = %d, want 1 -- an unbroken run is one episode", got.Runs)
+	}
+}
+
+// TestSilenceIsWhatIsCounted pins what an underrun actually does to the
+// waveform, which is the reason to count it at all.
+func TestSilenceIsWhatIsCounted(t *testing.T) {
+	t.Parallel()
+
+	bs := NewBufferedStreamer(stalledStreamer{}, 1024)
+	defer bs.Close()
+
+	buf := make([][2]float64, 64)
+	for i := range buf {
+		buf[i] = [2]float64{0.5, 0.5}
+	}
+
+	n, ok := bs.Stream(buf)
+	if !ok || n != len(buf) {
+		t.Fatalf("Stream = (%d, %v), want (%d, true)", n, ok, len(buf))
+	}
+
+	for i := range buf {
+		if buf[i] != ([2]float64{}) {
+			t.Fatalf("sample %d is %v, want silence", i, buf[i])
+		}
+	}
+
+	if got := bs.Underruns().Samples; got != int64(len(buf)) {
+		t.Errorf("counted %d samples of silence, wrote %d", got, len(buf))
+	}
+}
+
+// TestSeparateEpisodesAreSeparateRuns is the counter's whole shape:
+// audio arriving between two underruns makes them two, because that is
+// two interruptions and two clicks.
+func TestSeparateEpisodesAreSeparateRuns(t *testing.T) {
+	t.Parallel()
+
+	// A source that yields nothing until it is fed, so the ring can be
+	// emptied, filled and emptied again on demand.
+	src := &gatedStreamer{}
+
+	bs := NewBufferedStreamer(src, 1024)
+	defer bs.Close()
+
+	buf := make([][2]float64, 128)
+
+	starve := func() {
+		t.Helper()
+
+		for range 2 {
+			if _, ok := bs.Stream(buf); !ok {
+				t.Fatal("the stall budget ran out before the test did")
+			}
+		}
+	}
+
+	// feed lets exactly one bufferful through and drains it, so the
+	// ring is empty again on return. Allowing more would mean the
+	// starve() after it drained real audio instead of underrunning,
+	// which is what the first version of this test did -- it reported
+	// one episode and looked like the counter was wrong.
+	feed := func() {
+		t.Helper()
+
+		src.allow(len(buf))
+
+		// The read-ahead is a goroutine, so wait for real samples
+		// rather than assuming they have landed.
+		deadline := time.Now().Add(2 * time.Second)
+		for time.Now().Before(deadline) {
+			n, ok := bs.Stream(buf)
+			if ok && n > 0 && buf[0] != ([2]float64{}) {
+				return
+			}
+
+			time.Sleep(time.Millisecond)
+		}
+
+		t.Fatal("the source never delivered a sample")
+	}
+
+	starve()
+	feed()
+	starve()
+
+	if got := bs.Underruns().Runs; got < 2 {
+		t.Errorf(
+			"Runs = %d, want at least 2 -- audio in between makes two "+
+				"episodes, not one",
+			got,
+		)
+	}
+}
+
+// TestTheStallResetDoesNotClearTheCounter is the regression this file
+// is really about.
+//
+// resetStarvationLocked runs on every arriving sample and on every
+// Flush. If it cleared the cumulative count too, the counter would
+// report zero on exactly the workload it exists to measure -- a stream
+// that underruns repeatedly but always recovers -- which is
+// indistinguishable from healthy playback and is what the code did
+// before #135.
+func TestTheStallResetDoesNotClearTheCounter(t *testing.T) {
+	t.Parallel()
+
+	bs := NewBufferedStreamer(stalledStreamer{}, 1024)
+	defer bs.Close()
+
+	buf := make([][2]float64, 128)
+
+	if _, ok := bs.Stream(buf); !ok {
+		t.Fatal("the stall budget ran out before the test did")
+	}
+
+	before := bs.Underruns()
+	if before.Runs == 0 {
+		t.Fatal("nothing was counted, so the reset cannot be tested")
+	}
+
+	// Both of the ways a run is forgotten.
+	bs.mu.Lock()
+	bs.resetStarvationLocked()
+	bs.mu.Unlock()
+
+	bs.Flush()
+
+	if got := bs.Underruns(); got != before {
+		t.Errorf(
+			"forgetting the stall run also discarded the count: %+v, "+
+				"want %+v",
+			got, before,
+		)
+	}
+}
+
+// TestUnderrunDeltaNeverGoesBackwards covers the one arithmetic trap in
+// the reporting side.
+//
+// The counter belongs to the streamer and the streamer is replaced on
+// every track, so a baseline carried across a track change is the
+// previous track's total subtracted from a fresh zero. The load path
+// resets the baseline, and this clamps as well -- a negative count in a
+// log line reads as a broken instrument, which would discredit the
+// measurement rather than merely mis-state it.
+func TestUnderrunDeltaNeverGoesBackwards(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name string
+		now  UnderrunStats
+		last UnderrunStats
+		want UnderrunStats
+	}{
+		{
+			name: "ordinary progress",
+			now:  UnderrunStats{Runs: 5, Calls: 40, Samples: 4000},
+			last: UnderrunStats{Runs: 2, Calls: 10, Samples: 1000},
+			want: UnderrunStats{Runs: 3, Calls: 30, Samples: 3000},
+		},
+		{
+			name: "nothing happened",
+			now:  UnderrunStats{Runs: 5, Calls: 40, Samples: 4000},
+			last: UnderrunStats{Runs: 5, Calls: 40, Samples: 4000},
+			want: UnderrunStats{},
+		},
+		{
+			name: "a new streamer, with a stale baseline",
+			now:  UnderrunStats{},
+			last: UnderrunStats{Runs: 9, Calls: 90, Samples: 9000},
+			want: UnderrunStats{},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			if got := underrunDelta(tt.now, tt.last); got != tt.want {
+				t.Errorf("underrunDelta = %+v, want %+v", got, tt.want)
+			}
+		})
+	}
+}
+
+// gatedStreamer produces only what it has been allowed to, and
+// otherwise stalls without ending -- so a test can decide exactly when
+// the ring runs dry.
+type gatedStreamer struct {
+	mu        sync.Mutex
+	remaining int
+}
+
+func (g *gatedStreamer) allow(n int) {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+
+	g.remaining += n
+}
+
+func (g *gatedStreamer) Stream(samples [][2]float64) (int, bool) {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+
+	if g.remaining <= 0 {
+		return 0, true
+	}
+
+	n := min(len(samples), g.remaining)
+
+	for i := range n {
+		samples[i] = [2]float64{0.25, 0.25}
+	}
+
+	g.remaining -= n
+
+	return n, true
+}
+
+func (g *gatedStreamer) Err() error { return nil }

backend/player/player.go

@@ -39,16 +39,21 @@ type Player struct {
 	// via the queue).
 	mu sync.Mutex
 
-	ctx                     context.Context
+	ctx          context.Context
-	logger                  *slog.Logger
+	logger       *slog.Logger
-	db                      *database.DB
+	db           *database.DB
-	state                   State
+	state        State
-	currentFile             *os.File
+	currentFile  *os.File
-	format                  beep.Format
+	format       beep.Format
-	baseStreamer            beep.Streamer
+	baseStreamer beep.Streamer
-	seeker                  beep.StreamSeeker
+	seeker       beep.StreamSeeker
-	resampled               beep.Streamer
+	resampled    beep.Streamer
-	buffered                *BufferedStreamer
+	buffered     *BufferedStreamer
+
+	// lastUnderruns is the previous report, so the 1 Hz log can say
+	// what happened in the last second and stay quiet when nothing did.
+	// It is reset with the streamer, in loadFileLocked.
+	lastUnderruns           UnderrunStats
 	control                 *beep.Ctrl
 	volume                  *effects.Volume
 	speakerStreamer         beep.Streamer
@@ -71,6 +76,19 @@ type Player struct {
 	// not something the user chose.
 	duckAmount float64
 
+	// systemVolume is what SystemOwnsVolume answers: the platform's own
+	// control is the only one, so ours neither acts nor persists.  It is
+	// a field rather than the build constant read directly so that a
+	// test can exercise both sides on any machine.  See systemvolume.go.
+	systemVolume bool
+
+	// storedVolume and storedMuted hold the persisted level as it was
+	// found at restore, for a platform whose volume we do not own: the
+	// maximum we then run at is not a level the user chose, so saveState
+	// writes back what it read rather than overwriting it.
+	storedVolume UserVolume
+	storedMuted  bool
+
 	// trackLengthMs holds the authoritative track duration in
 	// milliseconds, sourced from the database (which uses the
 	// custom header parser).  The go-mp3 decoder's Len() can be
@@ -156,6 +174,8 @@ func NewPlayer(logger *slog.Logger, db *database.DB) *Player {
 		logger:       logger,
 		db:           db,
 		state:        Stopped,
+		systemVolume: platformOwnsVolume,
+		storedVolume: DefaultUserVol,
 		baseStreamer: generators.Silence(-1),
 		format: beep.Format{
 			SampleRate: speakerSampleRate,
@@ -277,9 +297,78 @@ func (p *Player) emitPositionIfPlaying() {
 		return
 	}
 
+	p.reportUnderrunsLocked()
 	p.emitPositionLocked()
 }
 
+// underrunDelta is what happened since the last report.
+//
+// It clamps at zero rather than subtracting blind, because the counter
+// belongs to the *streamer* and the streamer is replaced on every
+// track: a baseline carried across that boundary is the previous
+// track's total subtracted from a fresh zero, which is negative. That
+// is repaired at the load (lastUnderruns is reset with the streamer)
+// and clamped here as well, because a negative count in a log line
+// reads as a broken instrument and would discredit the measurement
+// this exists to make.
+func underrunDelta(now, last UnderrunStats) UnderrunStats {
+	return UnderrunStats{
+		Runs:    max(0, now.Runs-last.Runs),
+		Calls:   max(0, now.Calls-last.Calls),
+		Samples: max(0, now.Samples-last.Samples),
+	}
+}
+
+// reportUnderrunsLocked logs what the ring buffer missed, at most once
+// a second and only when the number moved.  Must be called with p.mu
+// held.
+//
+// **An underrun is audible and nothing counted it** (#135). The ring
+// serves silence when it is empty, so a run of zeros is spliced into
+// the waveform and the step discontinuity at each edge is a click; a
+// series of short ones is static. Everything that makes one likelier
+// is worse on a phone than on a desktop -- slower storage, a governor
+// that parks cores, background work, GC -- and no tier here can see it,
+// since CI's audio device is a null sink chosen because it keeps time.
+//
+// Three things about the reporting are deliberate.
+//
+// **It is on the 1 Hz position ticker rather than in Stream.** Stream
+// runs on the speaker callback's real-time deadline, and a log line
+// there would allocate, format and write on the exact path whose
+// missed deadline is the defect -- measuring by making it worse.
+//
+// **An unchanged count is not logged.** That is emitStatus' rule one
+// package over: a healthy player is silent, so anything in the log is
+// news, and the line appears exactly while it is popping. Reading it
+// off a device means `make android-logs` with the audio audible.
+//
+// **It is Info rather than Debug**, because the default level is Info
+// and a phone has no convenient way to set YJ_LOG_LEVEL -- a debug
+// line here would be a counter nobody on the affected platform can
+// read, which is the shape of the bug that made #160 necessary.
+func (p *Player) reportUnderrunsLocked() {
+	if p.buffered == nil {
+		return
+	}
+
+	stats := p.buffered.Underruns()
+	if stats == p.lastUnderruns {
+		return
+	}
+
+	since := underrunDelta(stats, p.lastUnderruns)
+	p.lastUnderruns = stats
+
+	slog.Info("audio underrun",
+		"runs", since.Runs,
+		"calls", since.Calls,
+		"silenceMs", speakerSampleRate.D(int(since.Samples)).Milliseconds(),
+		"trackRuns", stats.Runs,
+		"trackSilenceMs", speakerSampleRate.D(int(stats.Samples)).Milliseconds(),
+	)
+}
+
 // emitPositionLocked pushes the current position to the frontend.
 // Must be called with p.mu held.
 func (p *Player) emitPositionLocked() {
@@ -469,6 +558,12 @@ func (p *Player) updateStreamers(
 		p.resampled, int(speakerSampleRate)*2,
 	)
 
+	// The counter belongs to the streamer, so the baseline it is
+	// reported against has to go with it -- otherwise the first report
+	// of a new track is the previous track's total subtracted from
+	// zero, which is negative and looks like the instrument is broken.
+	p.lastUnderruns = UnderrunStats{}
+
 	// wrap in ctrl streamer to allow play/pause
 	p.control = &beep.Ctrl{Streamer: p.buffered}
 
@@ -875,6 +970,10 @@ func (p *Player) SetVolume(desiredVolume UserVolume) {
 	p.mu.Lock()
 	defer p.mu.Unlock()
 
+	if p.systemVolume {
+		return
+	}
+
 	p.setVolumeLocked(desiredVolume)
 	p.emitVolumeChanged()
 	p.saveState()
@@ -923,6 +1022,10 @@ func (p *Player) ChangeVolume(deltaVolume int) error {
 	p.mu.Lock()
 	defer p.mu.Unlock()
 
+	if p.systemVolume {
+		return nil
+	}
+
 	p.setVolumeLocked(p.getUserVolume() + UserVolume(deltaVolume))
 	p.emitVolumeChanged()
 	p.saveState()
@@ -953,6 +1056,14 @@ func (p *Player) MuteToggle() error {
 		return errNoAudioFileLoaded
 	}
 
+	// Mute is a level of zero by another name, so it goes with the rest
+	// of the volume where the system owns it -- and it would be the one
+	// state on such a platform the user could not get out of, since with
+	// no control rendered there is nothing left to un-mute with.
+	if p.systemVolume {
+		return nil
+	}
+
 	speaker.Lock()
 	p.volume.Silent = !p.volume.Silent
 	speaker.Unlock()
@@ -1403,7 +1514,15 @@ func (p *Player) saveState() {
 	volume := int64(DefaultUserVol)
 	muted := false
 
-	if p.volume != nil {
+	switch {
+	case p.systemVolume:
+		// The maximum this platform runs at is not a level anybody
+		// chose, so it is not one to remember.  Writing back what
+		// restore found keeps the row a description of the user's
+		// setting without needing a second query that omits the column.
+		volume = int64(p.storedVolume)
+		muted = p.storedMuted
+	case p.volume != nil:
 		volume = int64(p.getUserVolume())
 		muted = p.volume.Silent
 	}
@@ -1487,11 +1606,20 @@ func (p *Player) restoreStateLocked() {
 		}
 	}
 
-	vol := clampVolume(UserVolume(state.Volume))
+	if p.systemVolume {
-	p.setVolumeLocked(vol)
+		// Remembered, not applied: the device's keys are the volume
+		// control here, so the player runs wide open and hands the
+		// stored level back untouched at the next save.
+		p.storedVolume = clampVolume(UserVolume(state.Volume))
+		p.storedMuted = state.Muted
+		p.setVolumeLocked(MaxUserVol)
+	} else {
+		vol := clampVolume(UserVolume(state.Volume))
+		p.setVolumeLocked(vol)
 
-	if state.Muted {
+		if state.Muted {
-		p.volume.Silent = true
+			p.volume.Silent = true
+		}
 	}
 
 	// Restore last track if the file still exists.
@@ -1531,8 +1659,9 @@ func (p *Player) restoreStateLocked() {
 	}
 
 	p.logger.Info("Player state restored",
-		"volume", vol,
+		"volume", p.getUserVolume(),
-		"muted", state.Muted,
+		"muted", p.volume.Silent,
+		"systemVolume", p.systemVolume,
 		"trackPath", state.LastTrackPath,
 		"positionSeconds", state.LastPositionSeconds,
 	)

backend/player/systemvolume.go

@@ -0,0 +1,42 @@
+package player
+
+// Who owns the volume, and what follows when it is not us.
+//
+// On Android the hardware keys *are* the volume control and the
+// framework mixes our stream against the device level, so a second
+// control inside the app is a slider that moves something the user
+// already moved (#64).  Where that is true the player's own level sits
+// at maximum, nothing changes it, and nothing persists it.
+//
+// **The predicate is named after the capability, not the platform.**
+// The frontend asks "is there a volume for me to control", which is a
+// question about this build; asking "is this a phone" instead would
+// key the answer to a viewport, and an Android tablet at 600px or more
+// would then draw the bottom bar's slider over a level pinned at
+// maximum -- a control that cannot act, which is the thing
+// `library-status-indicator` already settled is worse than none.
+//
+// **Only `platformOwnsVolume` is behind a build tag**, in two files
+// that declare nothing else.  A tagged file is compiled by nothing
+// `make lint` or `make test` runs and is untestable off a phone, which
+// is the reasoning `mediacontrols/androidpayload.go` states for
+// keeping its contract out of one -- so everything decidable here is
+// decided against `Player.systemVolume`, a field a test sets either
+// way, and the tag decides only what that field starts as.
+//
+// The one thing this must not disturb is ducking.  `SetDuck` applies
+// its attenuation by re-applying the *user's* level through
+// `setVolumeLocked`, so pinning that level to maximum leaves the
+// offset arithmetic exactly as it was: an OS asking us to get out of
+// the way of a navigation prompt is not the user setting a volume, and
+// it is the only thing that may move the output on such a platform.
+
+// SystemOwnsVolume reports whether the platform's own control is the
+// only volume control there is, so this app neither offers one nor
+// remembers a level.
+//
+// It is bound: the frontend renders no `<volume-control>` when it is
+// true, at any width.
+func (p *Player) SystemOwnsVolume() bool {
+	return p.systemVolume
+}

backend/player/systemvolume_android.go

@@ -0,0 +1,11 @@
+//go:build android
+
+package player
+
+// platformOwnsVolume is true on Android: volume is the device's, set
+// with the hardware keys, and `mediacontrols`' Android handler
+// implements no volume callback for the same reason.
+//
+// See systemvolume.go for why this constant is the whole of what a
+// build tag decides here.
+const platformOwnsVolume = true

backend/player/systemvolume_other.go

@@ -0,0 +1,10 @@
+//go:build !android
+
+package player
+
+// platformOwnsVolume is false everywhere but Android: a desktop mixer
+// is per-application, so our level is the one the user reaches for.
+//
+// See systemvolume.go for why this constant is the whole of what a
+// build tag decides here.
+const platformOwnsVolume = false

backend/player/systemvolume_test.go

@@ -0,0 +1,215 @@
+package player
+
+import (
+	"log/slog"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/gopxl/beep/v2/effects"
+
+	"yellowjacket/backend/database"
+)
+
+// pinnedPlayer is a player on a platform whose volume belongs to the
+// device.  The field is set rather than the build constant read,
+// because the constant is true on exactly one platform and no tier
+// here runs on it -- see systemvolume.go.
+func pinnedPlayer(t *testing.T, db *database.DB) *Player {
+	t.Helper()
+
+	p := NewPlayer(slog.Default(), db)
+	p.systemVolume = true
+	p.volume = &effects.Volume{Base: 2}
+	p.setVolumeLocked(MaxUserVol)
+
+	return p
+}
+
+// TestSystemVolumeRefusesEveryWayToChangeTheLevel is the first half of
+// #64: where the device owns the volume, ours sits at maximum and none
+// of the three routes to a level moves it.  Mute is in that list
+// because it is a level of zero by another name, and because with no
+// control rendered it is the one state on such a platform there would
+// be nothing to get out of.
+func TestSystemVolumeRefusesEveryWayToChangeTheLevel(t *testing.T) {
+	t.Parallel()
+
+	p := pinnedPlayer(t, nil)
+
+	if !p.SystemOwnsVolume() {
+		t.Fatal("SystemOwnsVolume() = false on a pinned player")
+	}
+
+	if got := p.getUserVolume(); got != MaxUserVol {
+		t.Errorf("starting volume = %d, want %d", got, MaxUserVol)
+	}
+
+	p.SetVolume(20)
+
+	if got := p.getUserVolume(); got != MaxUserVol {
+		t.Errorf("volume after SetVolume(20) = %d, want %d", got, MaxUserVol)
+	}
+
+	if err := p.ChangeVolume(-30); err != nil {
+		t.Fatalf("ChangeVolume: %v", err)
+	}
+
+	if got := p.getUserVolume(); got != MaxUserVol {
+		t.Errorf("volume after ChangeVolume(-30) = %d, want %d", got, MaxUserVol)
+	}
+
+	if err := p.MuteToggle(); err != nil {
+		t.Fatalf("MuteToggle: %v", err)
+	}
+
+	if p.volume.Silent {
+		t.Error("MuteToggle silenced a player whose volume the system owns")
+	}
+}
+
+// TestAnUnpinnedPlayerStillChangesItsVolume is the other side of the
+// same switch.  Without it the test above passes on a player that
+// refuses everything, which is what a mis-wired field would produce.
+func TestAnUnpinnedPlayerStillChangesItsVolume(t *testing.T) {
+	t.Parallel()
+
+	p := NewPlayer(slog.Default(), nil)
+	p.volume = &effects.Volume{Base: 2}
+	p.setVolumeLocked(MaxUserVol)
+
+	if p.SystemOwnsVolume() {
+		t.Fatal("SystemOwnsVolume() = true off Android")
+	}
+
+	p.SetVolume(20)
+
+	if got := p.getUserVolume(); got != 20 {
+		t.Errorf("volume after SetVolume(20) = %d, want 20", got)
+	}
+
+	if err := p.MuteToggle(); err != nil {
+		t.Fatalf("MuteToggle: %v", err)
+	}
+
+	if !p.volume.Silent {
+		t.Error("MuteToggle did not silence an ordinary player")
+	}
+}
+
+// TestSystemVolumeStillDucks is the issue's second Finding, made a
+// test: pinning the user's level must leave the OS's attenuation
+// working, because a duck is not a volume the user chose and is the
+// only thing that may move the output on such a platform.
+func TestSystemVolumeStillDucks(t *testing.T) {
+	t.Parallel()
+
+	p := pinnedPlayer(t, nil)
+	open := p.volume.Volume
+
+	p.SetDuck(true)
+
+	if p.volume.Volume >= open {
+		t.Errorf(
+			"ducked output = %v, want less than %v", p.volume.Volume, open,
+		)
+	}
+
+	if got := p.getUserVolume(); got != MaxUserVol {
+		t.Errorf("user volume while ducked = %d, want %d", got, MaxUserVol)
+	}
+
+	// A refused SetVolume must not disturb the offset either: it
+	// returns before setVolumeLocked, which is what re-applies it.
+	ducked := p.volume.Volume
+
+	p.SetVolume(10)
+
+	if p.volume.Volume != ducked {
+		t.Errorf(
+			"output after a refused SetVolume = %v, want %v",
+			p.volume.Volume, ducked,
+		)
+	}
+
+	p.SetDuck(false)
+
+	if p.volume.Volume != open {
+		t.Errorf("output after unduck = %v, want %v", p.volume.Volume, open)
+	}
+}
+
+// TestSystemVolumeWritesBackTheLevelItFound is the rest of the
+// Direction: "make sure nothing writes a persisted volume from that
+// platform".  The maximum the player runs at is synthetic, so saving
+// must not record it over whatever the row already said.
+func TestSystemVolumeWritesBackTheLevelItFound(t *testing.T) {
+	t.Parallel()
+
+	db := database.NewTestDB(t)
+
+	// A level set by some earlier, unpinned session.
+	writer := NewPlayer(slog.Default(), db)
+	writer.volume = &effects.Volume{Base: 2}
+	writer.setVolumeLocked(30)
+	writer.SaveState()
+
+	p := pinnedPlayer(t, db)
+	p.RestoreState()
+
+	if got := p.getUserVolume(); got != MaxUserVol {
+		t.Errorf("restored volume = %d, want %d (the level is pinned)", got, MaxUserVol)
+	}
+
+	if p.volume.Silent {
+		t.Error("restore muted a player whose volume the system owns")
+	}
+
+	p.SaveState()
+
+	state, err := db.Queries.GetPlayerState(db.Ctx)
+	if err != nil {
+		t.Fatalf("GetPlayerState: %v", err)
+	}
+
+	if state.Volume != 30 {
+		t.Errorf("persisted volume = %d, want 30 (untouched)", state.Volume)
+	}
+}
+
+// TestPlatformVolumeOwnershipIsDeclaredOncePerPlatform sweeps the
+// source, because the pair of tagged files is the one thing here no
+// tier compiles both halves of: `make lint` and `make test` build the
+// `!android` side only, so a deleted or edited android file fails
+// nothing until somebody has a phone in their hand.
+func TestPlatformVolumeOwnershipIsDeclaredOncePerPlatform(t *testing.T) {
+	t.Parallel()
+
+	want := map[string]string{
+		"systemvolume_other.go":   "const platformOwnsVolume = false",
+		"systemvolume_android.go": "const platformOwnsVolume = true",
+	}
+
+	tags := map[string]string{
+		"systemvolume_other.go":   "//go:build !android",
+		"systemvolume_android.go": "//go:build android",
+	}
+
+	for name, decl := range want {
+		src, err := os.ReadFile(filepath.Join(".", name))
+		if err != nil {
+			t.Errorf("%s: %v", name, err)
+
+			continue
+		}
+
+		if !strings.Contains(string(src), decl) {
+			t.Errorf("%s does not declare %q", name, decl)
+		}
+
+		if !strings.Contains(string(src), tags[name]) {
+			t.Errorf("%s does not carry %q", name, tags[name])
+		}
+	}
+}

backend/riff/riff.go

@@ -0,0 +1,183 @@
+// Package riff reads the chunk layout of a RIFF/WAVE container.
+//
+// It exists because both halves of WAV tagging need it and neither can
+// import the other: backend/tagwriter writes a WAV's tags into a RIFF
+// "id3 " chunk and already imports backend/metadata, which is what has
+// to read them back out.  backend/tagtotals is the precedent.
+//
+// The two readers here are deliberately different.  Parse holds every
+// chunk's data in memory, which is what rewriting a file needs; a WAV's
+// audio *is* the "data" chunk, so doing that on the scan path would
+// read every library file in full.  ID3Chunk seeks over what it is not
+// looking for instead.  Both walk the same headers.
+package riff
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+)
+
+// Sentinel errors describing a container this package will not read.
+var (
+	ErrRF64NotSupported = errors.New("RF64 files are not yet supported")
+	ErrNotRIFF          = errors.New("not a RIFF file")
+	ErrNotWAVE          = errors.New("not a WAVE file")
+	ErrNoID3Chunk       = errors.New("no ID3 chunk in RIFF file")
+)
+
+// Chunk holds a single RIFF sub-chunk (ID + raw data).
+type Chunk struct {
+	ID   [4]byte
+	Data []byte
+}
+
+// IsID3 reports whether id is that of an ID3v2 RIFF chunk.  Both
+// lowercase "id3 " and uppercase "ID3 " are accepted.
+func IsID3(id [4]byte) bool {
+	return strings.ToLower(string(id[:3])) == "id3"
+}
+
+// Parse reads every RIFF sub-chunk from r, in order, starting at the
+// reader's current position.  It rejects RF64 files and non-WAVE
+// containers with descriptive errors.  The parser is lenient: it
+// tolerates a missing final padding byte and ignores the declared
+// RIFF size.
+func Parse(r io.Reader) ([]Chunk, error) {
+	if err := readContainer(r); err != nil {
+		return nil, err
+	}
+
+	var chunks []Chunk
+
+	for {
+		id, size, err := nextHeader(r)
+		if errors.Is(err, io.EOF) {
+			break
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		data := make([]byte, size)
+		if _, err := io.ReadFull(r, data); err != nil {
+			return nil, fmt.Errorf("read chunk data for %q: %w", id, err)
+		}
+
+		chunks = append(chunks, Chunk{ID: id, Data: data})
+
+		// Odd-length chunks have a padding byte.  Lenient: if the
+		// read fails (e.g. EOF), just break rather than error.
+		if size%2 != 0 {
+			var pad [1]byte
+
+			if _, err := r.Read(pad[:]); err != nil {
+				break
+			}
+		}
+	}
+
+	return chunks, nil
+}
+
+// ID3Chunk returns the payload of the ID3v2 chunk of the RIFF/WAVE
+// container at the reader's current position, seeking over every other
+// chunk rather than reading it.  It returns ErrNoID3Chunk when the
+// container carries no such chunk, and leaves the read position
+// unspecified either way.
+func ID3Chunk(r io.ReadSeeker) ([]byte, error) {
+	if err := readContainer(r); err != nil {
+		return nil, err
+	}
+
+	for {
+		id, size, err := nextHeader(r)
+		if errors.Is(err, io.EOF) {
+			return nil, ErrNoID3Chunk
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		if !IsID3(id) {
+			// Odd-length chunks carry a padding byte.  Seeking past
+			// the end of the file is not an error; the next header
+			// read is what reports the end.
+			if _, err := r.Seek(int64(size)+int64(size%2), io.SeekCurrent); err != nil {
+				return nil, fmt.Errorf("skip chunk %q: %w", id, err)
+			}
+
+			continue
+		}
+
+		// Copied rather than allocated up front: a truncated file is
+		// free to declare a chunk larger than the whole of itself.
+		var data bytes.Buffer
+		if _, err := io.CopyN(&data, r, int64(size)); err != nil {
+			return nil, fmt.Errorf("read chunk data for %q: %w", id, err)
+		}
+
+		return data.Bytes(), nil
+	}
+}
+
+// readContainer consumes the 12-byte RIFF/WAVE header at the reader's
+// current position.
+func readContainer(r io.Reader) error {
+	var magic [4]byte
+	if _, err := io.ReadFull(r, magic[:]); err != nil {
+		return fmt.Errorf("read RIFF magic: %w", err)
+	}
+
+	if string(magic[:]) == "RF64" {
+		return ErrRF64NotSupported
+	}
+
+	if string(magic[:]) != "RIFF" {
+		return fmt.Errorf("%w: got %q", ErrNotRIFF, magic)
+	}
+
+	// Read (and discard) RIFF size — lenient, do not enforce.
+	var riffSize uint32
+	if err := binary.Read(r, binary.LittleEndian, &riffSize); err != nil {
+		return fmt.Errorf("read RIFF size: %w", err)
+	}
+
+	var form [4]byte
+	if _, err := io.ReadFull(r, form[:]); err != nil {
+		return fmt.Errorf("read WAVE form type: %w", err)
+	}
+
+	if string(form[:]) != "WAVE" {
+		return fmt.Errorf("%w: got %q", ErrNotWAVE, form)
+	}
+
+	return nil
+}
+
+// nextHeader reads one sub-chunk header.  It returns io.EOF once the
+// chunks are exhausted, including for a header cut short.
+func nextHeader(r io.Reader) ([4]byte, uint32, error) {
+	var id [4]byte
+
+	_, err := io.ReadFull(r, id[:])
+	if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
+		return id, 0, io.EOF
+	}
+
+	if err != nil {
+		return id, 0, fmt.Errorf("read chunk ID: %w", err)
+	}
+
+	var size uint32
+	if err := binary.Read(r, binary.LittleEndian, &size); err != nil {
+		return id, 0, fmt.Errorf("read chunk size for %q: %w", id, err)
+	}
+
+	return id, size, nil
+}

backend/riff/riff_test.go

@@ -0,0 +1,211 @@
+package riff_test
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"testing"
+
+	"yellowjacket/backend/riff"
+)
+
+// chunk is one sub-chunk to put in a test container.
+type chunk struct {
+	id   string
+	data []byte
+}
+
+// buildRIFF assembles a container from magic, form type and chunks,
+// padding odd-length chunks the way a writer must.
+func buildRIFF(magic, form string, chunks []chunk) []byte {
+	var body bytes.Buffer
+
+	body.WriteString(form)
+
+	for _, c := range chunks {
+		body.WriteString(c.id)
+		_ = binary.Write(&body, binary.LittleEndian, uint32(len(c.data)))
+		body.Write(c.data)
+
+		if len(c.data)%2 != 0 {
+			body.WriteByte(0)
+		}
+	}
+
+	var out bytes.Buffer
+
+	out.WriteString(magic)
+	_ = binary.Write(&out, binary.LittleEndian, uint32(body.Len()))
+	out.Write(body.Bytes())
+
+	return out.Bytes()
+}
+
+func TestID3Chunk_FindsTheTagPastTheAudio(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		chunks []chunk
+		want   string
+	}{
+		{
+			name: "after an odd-length chunk",
+			chunks: []chunk{
+				{id: "fmt ", data: make([]byte, 16)},
+				{id: "LIST", data: []byte("INFOodd")},
+				{id: "data", data: make([]byte, 200)},
+				{id: "id3 ", data: []byte("ID3vTAG")},
+			},
+			want: "ID3vTAG",
+		},
+		{
+			// The chunk ID is written both ways in the wild, and the
+			// writer accepts either, so the reader must too.
+			name: "uppercase ID3",
+			chunks: []chunk{
+				{id: "data", data: make([]byte, 8)},
+				{id: "ID3 ", data: []byte("upper")},
+			},
+			want: "upper",
+		},
+		{
+			name: "first chunk",
+			chunks: []chunk{
+				{id: "id3 ", data: []byte("first")},
+				{id: "data", data: make([]byte, 8)},
+			},
+			want: "first",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			r := bytes.NewReader(buildRIFF("RIFF", "WAVE", tc.chunks))
+
+			got, err := riff.ID3Chunk(r)
+			if err != nil {
+				t.Fatalf("ID3Chunk: %v", err)
+			}
+
+			if string(got) != tc.want {
+				t.Errorf("chunk data: got %q, want %q", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestID3Chunk_RejectsWhatItCannotRead(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name  string
+		bytes []byte
+		want  error
+	}{
+		{
+			name:  "no ID3 chunk",
+			bytes: buildRIFF("RIFF", "WAVE", []chunk{{id: "data", data: []byte{1, 2}}}),
+			want:  riff.ErrNoID3Chunk,
+		},
+		{
+			name:  "no chunks at all",
+			bytes: buildRIFF("RIFF", "WAVE", nil),
+			want:  riff.ErrNoID3Chunk,
+		},
+		{
+			name:  "not RIFF",
+			bytes: []byte("ID3\x03\x00\x00\x00\x00\x00\x00\x00\x00"),
+			want:  riff.ErrNotRIFF,
+		},
+		{
+			name:  "not WAVE",
+			bytes: buildRIFF("RIFF", "AVI ", []chunk{{id: "id3 ", data: []byte("x")}}),
+			want:  riff.ErrNotWAVE,
+		},
+		{
+			name:  "RF64",
+			bytes: buildRIFF("RF64", "WAVE", []chunk{{id: "id3 ", data: []byte("x")}}),
+			want:  riff.ErrRF64NotSupported,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			_, err := riff.ID3Chunk(bytes.NewReader(tc.bytes))
+			if !errors.Is(err, tc.want) {
+				t.Errorf("ID3Chunk error: got %v, want %v", err, tc.want)
+			}
+		})
+	}
+}
+
+// A file cut short mid-chunk is a file with no tag, not a reason to
+// allocate the size it claims: the declared size is four bytes any
+// truncation can leave saying 4 GB.
+func TestID3Chunk_ToleratesATruncatedFile(t *testing.T) {
+	t.Parallel()
+
+	full := buildRIFF("RIFF", "WAVE", []chunk{
+		{id: "data", data: make([]byte, 64)},
+		{id: "id3 ", data: []byte("tag")},
+	})
+
+	t.Run("cut inside the audio", func(t *testing.T) {
+		t.Parallel()
+
+		_, err := riff.ID3Chunk(bytes.NewReader(full[:32]))
+		if !errors.Is(err, riff.ErrNoID3Chunk) {
+			t.Errorf("ID3Chunk error: got %v, want %v", err, riff.ErrNoID3Chunk)
+		}
+	})
+
+	t.Run("cut inside the tag", func(t *testing.T) {
+		t.Parallel()
+
+		if _, err := riff.ID3Chunk(bytes.NewReader(full[:len(full)-2])); err == nil {
+			t.Error("ID3Chunk: got nil error for a truncated tag chunk")
+		}
+	})
+}
+
+// Parse is the writer's half and reads every chunk into memory, which
+// is what preserving them needs.
+func TestParse_ReadsEveryChunkInOrder(t *testing.T) {
+	t.Parallel()
+
+	raw := buildRIFF("RIFF", "WAVE", []chunk{
+		{id: "fmt ", data: make([]byte, 16)},
+		{id: "LIST", data: []byte("INFOodd")},
+		{id: "id3 ", data: []byte("tag")},
+	})
+
+	chunks, err := riff.Parse(bytes.NewReader(raw))
+	if err != nil {
+		t.Fatalf("Parse: %v", err)
+	}
+
+	want := []string{"fmt ", "LIST", "id3 "}
+	if len(chunks) != len(want) {
+		t.Fatalf("chunk count: got %d, want %d", len(chunks), len(want))
+	}
+
+	for i, id := range want {
+		if got := string(chunks[i].ID[:]); got != id {
+			t.Errorf("chunk %d: got %q, want %q", i, got, id)
+		}
+	}
+
+	if !riff.IsID3(chunks[2].ID) || string(chunks[2].Data) != "tag" {
+		t.Errorf("id3 chunk: got %q", chunks[2].Data)
+	}
+
+	// The padding byte after an odd chunk is not part of its data.
+	if string(chunks[1].Data) != "INFOodd" {
+		t.Errorf("odd chunk data: got %q, want %q", chunks[1].Data, "INFOodd")
+	}
+}

backend/system/userdata.go

@@ -52,6 +52,75 @@ func UseHomeOverride(base string) {
 	_ = os.Setenv(envHomeOverride, base)
 }
 
+// envTempDir is the variable Go's os.TempDir() reads, and through it
+// every library in the process that asks for a temporary file.
+const envTempDir = "TMPDIR"
+
+// tempDirName is the subdirectory of the app's own storage that
+// becomes that answer.
+const tempDirName = "tmp"
+
+// UseTempDir gives the process a temporary directory that exists.
+//
+// **Android has no /tmp and hands an app no TMPDIR**, and Go's
+// os.TempDir() falls back to "/tmp" when the variable is unset -- so
+// every library in the process that wants scratch space is handed a
+// path that has never existed. SQLite is the one that noticed: an
+// INSERT ... SELECT large enough to spill returned
+// SQLITE_IOERR_GETTEMPPATH (disk I/O error 6410), which is how the
+// champion search index came to fail its rebuild on every launch while
+// the app otherwise looked healthy (#190).
+//
+// It is the *class* that is fixed here rather than that statement.
+// Anything that spills fails the same way on that platform -- large
+// sorts, large joins, VACUUM -- so the repair belongs at the process's
+// one answer to the question rather than at each caller. The
+// alternative considered was PRAGMA temp_store = MEMORY, which is
+// cheaper and more local and is a promise that every future spill fits
+// in RAM on a phone; the catalog is the largest thing in this app and
+// that is not a promise worth making silently.
+//
+// The rules are UseHomeOverride's, for the same reasons. **An empty
+// base is a no-op**, because that is what
+// application.Mobile.StoragePath() returns on desktop -- so this needs
+// no build tag and changes nothing off mobile, where /tmp is real. And
+// **an explicit TMPDIR wins**, so anyone who set one deliberately gets
+// what they asked for; nothing sets it on the platform this exists for.
+//
+// It returns its error rather than swallowing it because a temp
+// directory that could not be created is the same silent failure one
+// step earlier, and since #160 a log line on that platform is
+// something a person can actually read.
+func UseTempDir(base string) error {
+	if base == "" || os.Getenv(envTempDir) != "" {
+		return nil
+	}
+
+	dir := filepath.Join(base, tempDirName)
+
+	if err := os.MkdirAll(dir, os.ModePerm); err != nil {
+		return fmt.Errorf("could not make the temp directory %s: %w", dir, err)
+	}
+
+	// Writability is checked rather than assumed: the whole failure
+	// this repairs is a directory that is named and cannot be used, and
+	// MkdirAll on an existing unwritable directory succeeds.
+	probe, err := os.CreateTemp(dir, "probe")
+	if err != nil {
+		return fmt.Errorf("temp directory %s is not writable: %w", dir, err)
+	}
+
+	name := probe.Name()
+	_ = probe.Close()
+	_ = os.Remove(name)
+
+	if err := os.Setenv(envTempDir, dir); err != nil {
+		return fmt.Errorf("could not set %s: %w", envTempDir, err)
+	}
+
+	return nil
+}
+
 // getUserDirPath returns and creates the path for a user directory.
 func getUserDirPath(dt dirType) (string, error) {
 	path, err := resolveUserDirPath(dt)

backend/system/userdata_test.go

@@ -87,3 +87,116 @@ func TestUseHomeOverride(t *testing.T) {
 		})
 	}
 }
+
+// UseTempDir carries UseHomeOverride's two rules for the same reasons,
+// plus one of its own: the directory it names has to be usable.
+//
+// **The only tier that can compile the platform this exists for is a
+// phone**, so everything decidable off one is decided here -- which is
+// androidpayload.go's discipline, and is why the platform call is a
+// parameter rather than something this package reaches for. The
+// device's half is a single measurement: no /tmp, no TMPDIR (#190).
+func TestUseTempDir(t *testing.T) {
+	t.Run("an empty base is a no-op", func(t *testing.T) {
+		// This is the desktop case in full: StoragePath() answers ""
+		// off mobile, where /tmp is real and must be left alone.
+		t.Setenv(envTempDir, "")
+
+		if err := UseTempDir(""); err != nil {
+			t.Fatalf("UseTempDir(\"\") = %v, want nil", err)
+		}
+
+		if got := os.Getenv(envTempDir); got != "" {
+			t.Errorf("%s = %q, want it untouched", envTempDir, got)
+		}
+	})
+
+	t.Run("an explicit TMPDIR wins", func(t *testing.T) {
+		const chosen = "/somewhere/deliberate"
+
+		// The base is taken before TMPDIR moves, because t.TempDir()
+		// reads TMPDIR too -- which is the same fact this function is
+		// about, met from the other side.
+		base := t.TempDir()
+
+		t.Setenv(envTempDir, chosen)
+
+		if err := UseTempDir(base); err != nil {
+			t.Fatalf("UseTempDir = %v, want nil", err)
+		}
+
+		if got := os.Getenv(envTempDir); got != chosen {
+			t.Errorf("%s = %q, want the explicit %q", envTempDir, got, chosen)
+		}
+	})
+
+	t.Run("points at a real directory under the base", func(t *testing.T) {
+		base := t.TempDir()
+
+		t.Setenv(envTempDir, "")
+
+		if err := UseTempDir(base); err != nil {
+			t.Fatalf("UseTempDir = %v, want nil", err)
+		}
+
+		got := os.Getenv(envTempDir)
+
+		want := filepath.Join(base, tempDirName)
+		if got != want {
+			t.Fatalf("%s = %q, want %q", envTempDir, got, want)
+		}
+
+		// The whole failure being repaired is a temp directory that is
+		// named and does not exist, so naming one is not enough.
+		info, err := os.Stat(got)
+		if err != nil {
+			t.Fatalf("the temp directory was named but not created: %v", err)
+		}
+
+		if !info.IsDir() {
+			t.Fatalf("%s is not a directory", got)
+		}
+	})
+
+	t.Run("os.TempDir then answers with it", func(t *testing.T) {
+		// The point of setting the variable at all: this is what every
+		// library in the process reads, SQLite's driver included.
+		base := t.TempDir()
+
+		t.Setenv(envTempDir, "")
+
+		if err := UseTempDir(base); err != nil {
+			t.Fatalf("UseTempDir = %v, want nil", err)
+		}
+
+		if got := os.TempDir(); got != filepath.Join(base, tempDirName) {
+			t.Errorf("os.TempDir() = %q, want the directory we made", got)
+		}
+	})
+
+	t.Run("an unwritable directory is an error, not a silent success", func(t *testing.T) {
+		if os.Getuid() == 0 {
+			t.Skip("root can write anywhere, so there is nothing to refuse")
+		}
+
+		base := t.TempDir()
+
+		// MkdirAll on an existing directory succeeds whatever its
+		// mode, so without the write probe this case would set TMPDIR
+		// to a directory nothing can use -- which is the bug again,
+		// one directory over.
+		if err := os.Mkdir(filepath.Join(base, tempDirName), 0o500); err != nil {
+			t.Fatalf("prepare the unwritable directory: %v", err)
+		}
+
+		t.Setenv(envTempDir, "")
+
+		if err := UseTempDir(base); err == nil {
+			t.Fatal("UseTempDir accepted a directory it cannot write to")
+		}
+
+		if got := os.Getenv(envTempDir); got != "" {
+			t.Errorf("%s was set to %q despite the failure", envTempDir, got)
+		}
+	})
+}

backend/tagwriter/totals_test.go

@@ -13,9 +13,10 @@ import (
 // indistinguishable from never having written one.  So these assert the
 // round trip through the *reader the scan uses*, not the bytes.
 //
-// WAV is the exception and it is not this change's: dhowden/tag has no
+// WAV was the exception until #104 -- dhowden/tag has no RIFF reader,
-// RIFF reader at all, so metadata.ExtractTags cannot see a WAV's ID3
+// so metadata.ExtractTags could not see a WAV's ID3 chunk and this
-// chunk -- which is why every other test here reads that chunk itself.
+// case read the chunk itself, which is a test of the writer wearing
+// the shape of a round trip.  All four go through the scanner now.
 func TestWriteTotals_RoundTripsInEveryFormat(t *testing.T) {
 	t.Parallel()
 
@@ -91,7 +92,7 @@ func TestWriteTotals_RoundTripsInEveryFormat(t *testing.T) {
 		},
 		{
 			name: "wav",
-			read: readWavID3Tags,
+			read: viaScanner,
 			write: func(t *testing.T, dir string) string {
 				t.Helper()
 

backend/tagwriter/wav.go

@@ -8,116 +8,22 @@ import (
 	"io"
 	"log/slog"
 	"os"
-	"strings"
 
 	id3v2 "github.com/bogem/id3v2/v2"
 
 	"yellowjacket/backend/fileutil"
+	"yellowjacket/backend/riff"
 )
 
-// Sentinel errors for WAV RIFF operations.
+// errFileTooLargeForWAV is the one RIFF error that belongs to the
-var (
+// writer; reading rejects a container in backend/riff.
-	errRF64NotSupported   = errors.New("RF64 files are not yet supported")
+var errFileTooLargeForWAV = errors.New("file too large for WAV format (>4GB)")
-	errNotRIFF            = errors.New("not a RIFF file")
-	errNotWAVE            = errors.New("not a WAVE file")
-	errFileTooLargeForWAV = errors.New("file too large for WAV format (>4GB)")
-)
-
-// riffChunk holds a single RIFF sub-chunk (ID + raw data).
-type riffChunk struct {
-	id   [4]byte
-	data []byte
-}
-
-// parseRIFF reads all RIFF sub-chunks from r.  It rejects RF64 files
-// and non-WAVE containers with descriptive errors.  The parser is
-// lenient on read: it tolerates missing padding bytes and ignores
-// the declared RIFF size.
-func parseRIFF(r io.ReadSeeker) ([]riffChunk, error) {
-	// Read 4-byte container magic.
-	var magic [4]byte
-	if _, err := io.ReadFull(r, magic[:]); err != nil {
-		return nil, fmt.Errorf("read RIFF magic: %w", err)
-	}
-
-	if string(magic[:]) == "RF64" {
-		return nil, errRF64NotSupported
-	}
-
-	if string(magic[:]) != "RIFF" {
-		return nil, fmt.Errorf("%w: got %q", errNotRIFF, magic)
-	}
-
-	// Read (and discard) RIFF size — lenient, do not enforce.
-	var riffSize uint32
-	if err := binary.Read(r, binary.LittleEndian, &riffSize); err != nil {
-		return nil, fmt.Errorf("read RIFF size: %w", err)
-	}
-
-	// Read 4-byte form type.
-	var form [4]byte
-	if _, err := io.ReadFull(r, form[:]); err != nil {
-		return nil, fmt.Errorf("read WAVE form type: %w", err)
-	}
-
-	if string(form[:]) != "WAVE" {
-		return nil, fmt.Errorf("%w: got %q", errNotWAVE, form)
-	}
-
-	// Read sub-chunks until EOF.
-	var chunks []riffChunk
-
-	for {
-		var chunkID [4]byte
-
-		_, err := io.ReadFull(r, chunkID[:])
-		if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
-			break
-		}
-
-		if err != nil {
-			return nil, fmt.Errorf("read chunk ID: %w", err)
-		}
-
-		var chunkSize uint32
-		if err := binary.Read(r, binary.LittleEndian, &chunkSize); err != nil {
-			return nil, fmt.Errorf("read chunk size for %q: %w", chunkID, err)
-		}
-
-		data := make([]byte, chunkSize)
-		if _, err := io.ReadFull(r, data); err != nil {
-			return nil, fmt.Errorf("read chunk data for %q: %w", chunkID, err)
-		}
-
-		chunks = append(chunks, riffChunk{id: chunkID, data: data})
-
-		// Odd-length chunks have a padding byte.  Lenient: if the
-		// read fails (e.g. EOF), just break rather than error.
-		if chunkSize%2 != 0 {
-			var pad [1]byte
-
-			if _, err := r.Read(pad[:]); err != nil {
-				break
-			}
-		}
-	}
-
-	return chunks, nil
-}
-
-// isID3ChunkID returns true if id represents an ID3v2 RIFF chunk.
-// Both lowercase "id3 " and uppercase "ID3 " are accepted.
-func isID3ChunkID(id [4]byte) bool {
-	s := strings.ToLower(string(id[:3]))
-
-	return s == "id3"
-}
 
 // writeRIFF writes a complete RIFF/WAVE container to w, preserving
 // the given chunks in order and appending the id3Data as the final
 // "id3 " chunk.  Returns errFileTooLargeForWAV if the result would
 // exceed the 4 GB RIFF limit.
-func writeRIFF(w io.Writer, chunks []riffChunk, id3Data []byte) error {
+func writeRIFF(w io.Writer, chunks []riff.Chunk, id3Data []byte) error {
 	// Calculate total RIFF payload size:
 	//   4 bytes (WAVE form type)
 	// + for each preserved chunk: 8 (header) + len(data) + padding
@@ -125,7 +31,7 @@ func writeRIFF(w io.Writer, chunks []riffChunk, id3Data []byte) error {
 	riffPayload := uint64(4)
 
 	for _, c := range chunks {
-		sz := uint64(len(c.data))
+		sz := uint64(len(c.Data))
 		riffPayload += 8 + sz
 
 		if sz%2 != 0 {
@@ -162,7 +68,7 @@ func writeRIFF(w io.Writer, chunks []riffChunk, id3Data []byte) error {
 
 	// Write each preserved chunk.
 	for _, c := range chunks {
-		if err := writeChunk(w, c.id, c.data); err != nil {
+		if err := writeChunk(w, c.ID, c.Data); err != nil {
 			return err
 		}
 	}
@@ -225,7 +131,7 @@ func writeWavTags(
 		return fmt.Errorf("open wav for reading: %w", err)
 	}
 
-	allChunks, err := parseRIFF(f)
+	allChunks, err := riff.Parse(f)
 
 	// Close immediately — we need the handle released before
 	// AtomicWrite creates the replacement file.
@@ -237,13 +143,13 @@ func writeWavTags(
 
 	// Separate preserved chunks from existing ID3 data.
 	var (
-		preserved   []riffChunk
+		preserved   []riff.Chunk
 		existingID3 []byte
 	)
 
 	for _, c := range allChunks {
-		if isID3ChunkID(c.id) {
+		if riff.IsID3(c.ID) {
-			existingID3 = c.data
+			existingID3 = c.Data
 		} else {
 			preserved = append(preserved, c)
 		}

backend/tagwriter/wav_test.go

@@ -12,6 +12,7 @@ import (
 	id3v2 "github.com/bogem/id3v2/v2"
 
 	"yellowjacket/backend/metadata"
+	"yellowjacket/backend/riff"
 )
 
 // createTestWAV builds a minimal valid WAV file with an optional
@@ -270,6 +271,88 @@ func TestWriteWavTags_PartialUpdate(t *testing.T) {
 	assertStrField(t, "Composer", meta.Composer, "Original Composer")
 }
 
+// The writer has always been correct and the reader could not see it:
+// a WAV tagged by this app scanned as an untagged file, so editing
+// tags, autotagging a folder or importing a WAV download all appeared
+// to work and changed nothing the library could show (#104).  So this
+// asserts the write through metadata.ExtractTags -- the reader the
+// scan uses -- rather than through the id3 chunk.
+func TestWriteWavTags_ReadBackByTheScanner(t *testing.T) {
+	t.Parallel()
+
+	dir := t.TempDir()
+	path := createTestWAV(t, dir, "scanner.wav", nil)
+	art := tinyJPEG(t)
+
+	changes := TagChanges{
+		FieldTitle:       "Some Song",
+		FieldArtist:      "Some Artist",
+		FieldAlbum:       "Some Album",
+		FieldAlbumArtist: "Some Album Artist",
+		FieldGenre:       "Rock",
+		FieldYear:        2024,
+		FieldTrackNumber: 3,
+		FieldComposer:    "Some Composer",
+		FieldCoverArt:    art,
+	}
+
+	if err := writeWavTags(testLogger(), path, changes); err != nil {
+		t.Fatalf("writeWavTags: %v", err)
+	}
+
+	meta, err := metadata.ExtractTags(path)
+	if err != nil {
+		t.Fatalf("ExtractTags: %v", err)
+	}
+
+	if meta.TagReadWarning != nil {
+		t.Errorf("TagReadWarning: %v", meta.TagReadWarning)
+	}
+
+	assertStrField(t, "Title", meta.Title, "Some Song")
+	assertStrField(t, "Artist", meta.Artist, "Some Artist")
+	assertStrField(t, "Album", meta.Album, "Some Album")
+	assertStrField(t, "AlbumArtist", meta.AlbumArtist, "Some Album Artist")
+	assertStrField(t, "Genre", meta.Genre, "Rock")
+	assertStrField(t, "Composer", meta.Composer, "Some Composer")
+	assertStrField(t, "FileFormat", meta.FileFormat, "WAV")
+	assertIntField(t, "Year", meta.Year, 2024)
+	assertIntField(t, "TrackNumber", meta.TrackNumber, 3)
+
+	if !strings.HasPrefix(meta.TagFormat, "ID3v2") {
+		t.Errorf("TagFormat: got %q, want an ID3v2 version", meta.TagFormat)
+	}
+
+	if meta.Picture == nil {
+		t.Fatal("expected cover art, got nil")
+	}
+
+	if !bytes.Equal(meta.Picture.Data, art) {
+		t.Errorf("picture data mismatch: got %d bytes, want %d",
+			len(meta.Picture.Data), len(art))
+	}
+}
+
+// An untagged WAV is a file with no tags, not a file with a problem:
+// the scanner falls back to the filename and must not be handed a
+// warning to surface about it.
+func TestUntaggedWav_ReadsAsEmptyWithoutAWarning(t *testing.T) {
+	t.Parallel()
+
+	path := createTestWAV(t, t.TempDir(), "bare.wav", nil)
+
+	meta, err := metadata.ExtractTags(path)
+	if err != nil {
+		t.Fatalf("ExtractTags: %v", err)
+	}
+
+	if meta.TagReadWarning != nil {
+		t.Errorf("TagReadWarning: %v", meta.TagReadWarning)
+	}
+
+	assertStrField(t, "Title", meta.Title, "")
+}
+
 func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 	t.Parallel()
 
@@ -282,7 +365,7 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 		t.Fatalf("open original: %v", err)
 	}
 
-	origChunks, err := parseRIFF(origFile)
+	origChunks, err := riff.Parse(origFile)
 	_ = origFile.Close()
 
 	if err != nil {
@@ -292,7 +375,7 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 	// Record original chunk data by ID string.
 	origData := map[string][]byte{}
 	for _, c := range origChunks {
-		origData[string(c.id[:])] = c.data
+		origData[string(c.ID[:])] = c.Data
 	}
 
 	// Write a tag to trigger RIFF rewrite.
@@ -309,7 +392,7 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 		t.Fatalf("open after write: %v", err)
 	}
 
-	newChunks, err := parseRIFF(newFile)
+	newChunks, err := riff.Parse(newFile)
 	_ = newFile.Close()
 
 	if err != nil {
@@ -320,7 +403,7 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 	origNonID3 := 0
 
 	for _, c := range origChunks {
-		if !isID3ChunkID(c.id) {
+		if !riff.IsID3(c.ID) {
 			origNonID3++
 		}
 	}
@@ -328,7 +411,7 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 	newNonID3 := 0
 
 	for _, c := range newChunks {
-		if !isID3ChunkID(c.id) {
+		if !riff.IsID3(c.ID) {
 			newNonID3++
 		}
 	}
@@ -359,17 +442,17 @@ func TestWriteWavTags_ChunkPreservation(t *testing.T) {
 // in chunks and its data matches want byte-for-byte.
 func checkChunkPreserved(
 	t *testing.T,
-	chunks []riffChunk,
+	chunks []riff.Chunk,
 	idStr string,
 	want []byte,
 ) {
 	t.Helper()
 
 	for _, c := range chunks {
-		if string(c.id[:]) == idStr {
+		if string(c.ID[:]) == idStr {
-			if !bytes.Equal(c.data, want) {
+			if !bytes.Equal(c.Data, want) {
 				t.Errorf("chunk %q data changed: got %d bytes, want %d",
-					idStr, len(c.data), len(want))
+					idStr, len(c.Data), len(want))
 			}
 
 			return
@@ -430,7 +513,7 @@ func TestWriteWavTags_RejectsRF64(t *testing.T) {
 	buf.WriteString("WAVE")
 
 	// Minimal ds64 chunk (required for RF64 but we just need
-	// enough bytes for parseRIFF to hit the RF64 rejection).
+	// enough bytes for riff.Parse to hit the RF64 rejection).
 	buf.WriteString("ds64")
 	_ = binary.Write(&buf, binary.LittleEndian, uint32(28)) //nolint:mnd
 	buf.Write(make([]byte, 28))                             //nolint:mnd
@@ -454,9 +537,12 @@ func TestWriteWavTags_RejectsRF64(t *testing.T) {
 
 // readWavID3Tags extracts ID3v2 metadata from a WAV file by parsing
 // the RIFF structure and reading the id3 chunk with bogem/id3v2.
-// dhowden/tag's ReadFrom does not support WAV files, and its
+//
-// ReadID3v2Tags fails on empty tags (after clearing all frames).
+// metadata.ExtractTags reads a WAV since #104 and is what the round
-// Using bogem/id3v2.ParseReader handles all cases correctly.
+// trips assert through.  This stays for the two cases that are about
+// the bytes rather than about the scan: a tag with every frame
+// cleared, which no reader reports as anything, and the chunk
+// preservation test, which is already parsing the container itself.
 func readWavID3Tags(
 	t *testing.T,
 	path string,
@@ -470,17 +556,17 @@ func readWavID3Tags(
 
 	defer func() { _ = f.Close() }()
 
-	chunks, err := parseRIFF(f)
+	chunks, err := riff.Parse(f)
 	if err != nil {
-		t.Fatalf("parseRIFF: %v", err)
+		t.Fatalf("riff.Parse: %v", err)
 	}
 
 	// Find the id3 chunk.
 	var id3Data []byte
 
 	for _, c := range chunks {
-		if isID3ChunkID(c.id) {
+		if riff.IsID3(c.ID) {
-			id3Data = c.data
+			id3Data = c.Data
 
 			break
 		}

e2e/specs/long-press.spec.ts

@@ -1,127 +0,0 @@
-import { test, expect } from '../support/fixtures.js';
-
-/**
- * Long-press is the touch route to a context menu (plan 016 B2 phase 3).
- *
- * The component tier proves the gesture in isolation, against markup it
- * built itself. What it cannot prove is the half that made this one
- * listener instead of six: that the synthetic event reaches the handler
- * a *real* component bound — `track-list` delegates its `contextmenu`
- * on the `lit-virtualizer` rather than binding one per row — and that
- * the real `wa-popup` menu opens from it, which is a path with its own
- * history of opening and then refusing to work (see
- * `menu-keyboard.spec.ts`).
- *
- * The pointer events are dispatched rather than performed: this project
- * runs Desktop Chrome and Desktop Safari, neither of which has touch,
- * and a device tier does not exist. So this is honest about what it
- * checks — the app's own listeners, on the app's own DOM, from the
- * events a touch would produce — and not about a real finger.
- */
-
-/** A common small phone, as in `phone-shell.spec.ts`. */
-const PHONE = { width: 390, height: 844 };
-
-/** Comfortably past the module's 500ms hold. */
-const HELD = 900;
-
-type Page = import('@playwright/test').Page;
-
-/** The track list's menu panel, or null while it is not rendered. */
-const panel = (page: Page) =>
-  page.evaluate(() => {
-    const el = document
-      .querySelector('track-list')
-      ?.shadowRoot?.querySelector('.context-menu-panel');
-
-    if (!el) return null;
-
-    return {
-      role: el.getAttribute('role'),
-      label: el.getAttribute('aria-label'),
-      items: el.querySelectorAll('[role="menuitem"]').length,
-    };
-  });
-
-/**
- * Press the first track row, optionally dragging partway through — the
- * shape of a scroll that begins on a row, which must not open a menu.
- */
-async function pressFirstRow(
-  page: Page,
-  opts: { driftY?: number } = {},
-): Promise<void> {
-  await page.evaluate((drift) => {
-    // `.track-row`, not `[role="row"]`: the column header is a row too,
-    // and it is the *first* one -- a press on it is correctly ignored,
-    // which reads exactly like the gesture not working.
-    const row = document
-      .querySelector('track-list')
-      ?.shadowRoot?.querySelector('.track-row');
-
-    if (!row) throw new Error('no track row to press');
-
-    const box = row.getBoundingClientRect();
-    const x = Math.round(box.left + box.width / 2);
-    const y = Math.round(box.top + box.height / 2);
-    const send = (type: string, dy = 0) =>
-      row.dispatchEvent(
-        new PointerEvent(type, {
-          bubbles: true,
-          composed: true,
-          cancelable: true,
-          pointerType: 'touch',
-          isPrimary: true,
-          clientX: x,
-          clientY: y + dy,
-        }),
-      );
-
-    send('pointerdown');
-
-    if (drift) send('pointermove', drift);
-  }, opts.driftY ?? 0);
-}
-
-test.describe('long-press opens the track menu', () => {
-  test.beforeEach(async ({ app }) => {
-    await app.setViewportSize(PHONE);
-    await app.getByTestId('tab-tracks').click();
-    await expect(app.getByTestId('main-content')).toHaveAttribute(
-      'data-active-view',
-      'tracks',
-    );
-  });
-
-  test.afterEach(async ({ app }) => {
-    // Every other spec file runs against a desktop, and the viewport
-    // belongs to the shared context rather than to this file.
-    await app.setViewportSize({ width: 1440, height: 900 });
-  });
-
-  test('reaches the delegated handler and opens the real menu', async ({
-    app,
-  }) => {
-    await expect.poll(() => panel(app)).toBeNull();
-
-    await pressFirstRow(app);
-
-    await expect
-      .poll(() => panel(app), { timeout: HELD + 2000 })
-      .toMatchObject({ role: 'menu', label: 'Track actions' });
-
-    // The same panel Shift+F10 opens, items and all -- not an empty
-    // popup that happened to become visible.
-    expect((await panel(app))?.items).toBeGreaterThan(0);
-  });
-
-  test('does not open one for a press that turns into a scroll', async ({
-    app,
-  }) => {
-    await pressFirstRow(app, { driftY: 40 });
-
-    await app.waitForTimeout(HELD);
-
-    expect(await panel(app)).toBeNull();
-  });
-});

e2e/specs/native-touch-feel.spec.ts

@@ -0,0 +1,140 @@
+import { test, expect } from '../support/fixtures.js';
+
+/**
+ * The web view's own tap highlight, and what replaced it (#54).
+ *
+ * Two halves, and each is here because no other tier can see it.
+ *
+ * **The highlight is killed by one declaration on `html`**, which
+ * reaches the app's shadow roots because `-webkit-tap-highlight-color`
+ * is inherited and inheritance crosses a shadow boundary. That is a
+ * property of `index.css`, and `index.css` is loaded by the real app
+ * and by nothing else — the component tier mounts a component with no
+ * page stylesheet at all, which is the same reason the theme's ramps
+ * are invisible to it.
+ *
+ * **The press state is measured rather than read.** The component tier
+ * asserts the shape of the stylesheet (which rule is inside which
+ * query, and that the press selector carries a state class), because
+ * `:active` cannot be forced there. Here there is a real pointer: hold
+ * the button down on a real row of the real list and read what the row
+ * became. That is the assertion that would fail if the rule were
+ * hoisted, renamed, or lost to `.selected`.
+ *
+ * What neither half is, is the device. Chrome 113's WebView is where
+ * the grey box was reported and where a finger is; the numbers from it
+ * are on the PR.
+ */
+type Page = import('@playwright/test').Page;
+
+/** The phone this work was measured against, in CSS pixels. */
+const DEVICE = { width: 424, height: 439 };
+
+/** The computed tap-highlight colour of a node inside a shadow root. */
+const tapHighlight = (page: Page, host: string, inner: string) =>
+  page.evaluate(
+    ([hostSel, innerSel]) => {
+      const el = document
+        .querySelector(hostSel!)
+        ?.shadowRoot?.querySelector(innerSel!);
+
+      if (!el) return null;
+
+      return getComputedStyle(el).getPropertyValue(
+        '-webkit-tap-highlight-color',
+      );
+    },
+    [host, inner],
+  );
+
+test.describe('the tap highlight', () => {
+  test('is transparent inside a shadow root, from one rule on html', async ({
+    app,
+    browserName,
+  }) => {
+    await app.getByTestId('nav-tracks').click();
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'tracks',
+    );
+
+    const row = await tapHighlight(app, 'track-list', '.track-row');
+
+    expect(row).not.toBeNull();
+
+    // The property is a WebKit extension that only iOS honours, so an
+    // engine is free not to report one at all. Chromium always does —
+    // measured at rgba(0, 0, 0, 0.18) with the rule removed, which is
+    // the grey box the report describes — so the assertion is not
+    // skippable there, and nothing this app can do makes the property
+    // disappear on an engine that has it.
+    test.skip(
+      row === '',
+      `${browserName} reports no -webkit-tap-highlight-color to read`,
+    );
+
+    expect(row).toBe('rgba(0, 0, 0, 0)');
+  });
+});
+
+test.describe('the press state that replaced it', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await app.getByTestId('tab-tracks').click();
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'tracks',
+    );
+    await expect(app.locator('track-list').first()).toBeVisible();
+  });
+
+  test.afterEach(async ({ app }) => {
+    await app.mouse.up();
+    await app.setViewportSize({ width: 1440, height: 900 });
+  });
+
+  test('shows on the row being pressed, and on that row only', async ({
+    app,
+  }) => {
+    const rows = await app.evaluate(() => {
+      const found = document
+        .querySelector('track-list')
+        ?.shadowRoot?.querySelectorAll('.track-row');
+
+      if (!found || found.length < 2) return null;
+
+      const rect = found[1]!.getBoundingClientRect();
+
+      return {
+        x: Math.round(rect.x + rect.width / 2),
+        y: Math.round(rect.y + rect.height / 2),
+      };
+    });
+
+    expect(rows).not.toBeNull();
+
+    const backgrounds = () =>
+      app.evaluate(() => {
+        const found = document
+          .querySelector('track-list')!
+          .shadowRoot!.querySelectorAll('.track-row');
+
+        return {
+          pressed: getComputedStyle(found[1]!).backgroundColor,
+          neighbour: getComputedStyle(found[2]!).backgroundColor,
+        };
+      });
+
+    await app.mouse.move(rows!.x, rows!.y);
+    await app.mouse.down();
+
+    const held = await backgrounds();
+
+    // The press overlay, from the theme rather than from a literal in
+    // a component: rgba(255, 255, 255, 0.12) on both dark ramps.
+    expect(held.pressed).toBe('rgba(255, 255, 255, 0.12)');
+    expect(held.neighbour).not.toBe(held.pressed);
+
+    await app.mouse.up();
+  });
+});

e2e/specs/phone-album-page.spec.ts

@@ -0,0 +1,209 @@
+import { test, expect } from '../support/fixtures.js';
+import type { Page } from '@playwright/test';
+
+/**
+ * The album page on a phone (#66).
+ *
+ * Two faults, and neither was visible to `layout-overflow.spec.ts`:
+ * that spec asserts the *shell* needs no sideways scrolling, and the
+ * shell was correct throughout — `body.scrollWidth === clientWidth`
+ * while `explore-album-details` itself measured 443 inside a 424px box
+ * and clipped two of the album's three primary actions with its own
+ * `overflow: hidden`. So the measurement here is **per control against
+ * the component's box**, which is the same shape `top-bar-fit.spec.ts`
+ * needed for the same reason.
+ *
+ * The other half is the scroll: the page was a fixed header over a
+ * scrolling tracklist, so at the reference device's 424x439 the header
+ * owned 253 of the panel's 318px and the list scrolled in the 64 that
+ * were left. It is one scroll container below 600px, which is a
+ * property of the *host* rather than of `.content`.
+ *
+ * The engine is the caveat this tier cannot close: the reference device
+ * renders in Chrome 113 and this is Chromium/WebKit. A flex direction
+ * and a scroll container are nowhere near that engine's documented gaps
+ * (relaxed nesting, the Popover API, `light-dark()`), but "it renders
+ * at that size in Chromium" is not evidence about the phone.
+ */
+
+/** The phone this was measured on, in CSS pixels. */
+const DEVICE = { width: 424, height: 439 };
+
+const details = (page: Page) => page.locator('explore-album-details');
+
+/** The page's own boxes, read from inside its shadow root. */
+const geometry = (page: Page) =>
+  page.evaluate(() => {
+    const host = document.querySelector('explore-album-details');
+    const sr = host?.shadowRoot;
+
+    if (!host || !sr) return null;
+
+    const box = (sel: string) => {
+      const el = sr.querySelector(sel);
+
+      if (!el) return null;
+
+      const r = el.getBoundingClientRect();
+
+      return { width: Math.round(r.width), right: Math.round(r.right) };
+    };
+
+    const content = sr.querySelector('.content');
+
+    return {
+      hostWidth: host.clientWidth,
+      hostScrollWidth: host.scrollWidth,
+      // The host is the scroller below 600px, so the page is taller
+      // than its box rather than the tracklist being a window inside it.
+      hostScrolls: host.scrollHeight > host.clientHeight,
+      contentScrolls: content
+        ? content.scrollHeight > content.clientHeight
+        : null,
+      header: box('.album-header'),
+      play: box('[data-testid="album-play"]'),
+      shuffle: box('[data-testid="album-shuffle"]'),
+      queue: box('[data-testid="album-queue"]'),
+      title: (() => {
+        const el = sr.querySelector('.album-title-text');
+
+        return el ? el.scrollWidth <= el.clientWidth + 1 : null;
+      })(),
+    };
+  });
+
+test.describe('the album page on a phone', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await openFirstAlbum(app);
+  });
+
+  test.afterEach(async ({ app }) => {
+    await app.setViewportSize({ width: 1440, height: 900 });
+    await app.getByTestId('nav-tracks').click();
+  });
+
+  test('keeps every action inside its own box', async ({ app }) => {
+    const geo = await geometry(app);
+
+    expect(geo).not.toBeNull();
+    // "Shuffle album" ended at x=443 in a 424px component and could not
+    // be reached by any gesture; "Add to queue" at 440.
+    for (const action of ['play', 'shuffle', 'queue'] as const) {
+      expect(
+        geo?.[action],
+        `${action} is rendered`,
+      ).not.toBeNull();
+      expect(
+        geo?.[action]?.right ?? 0,
+        `${action} ends inside the page`,
+      ).toBeLessThanOrEqual(geo?.hostWidth ?? 0);
+    }
+
+    expect(geo?.hostScrollWidth).toBe(geo?.hostWidth);
+    expect(geo?.header?.width).toBe(geo?.hostWidth);
+  });
+
+  test('gives the title the row rather than one glyph of it', async ({
+    app,
+  }) => {
+    // `.album-info` was squeezed to 112px beside the art, so an album
+    // called *Glass Harbour* drew as `G…`. It carries `min-width: 0`
+    // and was shrinking as asked — the row had to stack.
+    expect(await geometry(app).then((g) => g?.title)).toBe(true);
+  });
+
+  test('scrolls as one page, with the header scrolling away', async ({
+    app,
+  }) => {
+    const before = await geometry(app);
+
+    expect(before?.hostScrolls).toBe(true);
+    expect(before?.contentScrolls).toBe(false);
+
+    const headerTop = () =>
+      app.evaluate(
+        () =>
+          document
+            .querySelector('explore-album-details')
+            ?.shadowRoot?.querySelector('.album-header')
+            ?.getBoundingClientRect().top ?? 0,
+      );
+
+    expect(await headerTop()).toBeGreaterThanOrEqual(0);
+
+    // A wheel gesture, not `scrollTop`: `overflow: hidden` still permits
+    // programmatic scrolling, so a probe that assigns it passes on the
+    // build this exists to fail.
+    await details(app).hover();
+    await app.mouse.wheel(0, 250);
+
+    await expect.poll(headerTop).toBeLessThan(-100);
+  });
+
+  test('is the desktop arrangement again above the breakpoint', async ({
+    app,
+  }) => {
+    await app.setViewportSize({ width: 1024, height: 800 });
+
+    // The same element, re-laid-out: one component with two
+    // arrangements, not a phone-only copy.
+    await expect
+      .poll(async () => (await geometry(app))?.hostScrolls)
+      .toBe(false);
+
+    const arrangement = await app.evaluate(() => {
+      const sr = document.querySelector('explore-album-details')?.shadowRoot;
+      const header = sr?.querySelector('.album-header');
+      const content = sr?.querySelector('.content');
+
+      return {
+        direction: header ? getComputedStyle(header).flexDirection : null,
+        contentOverflow: content ? getComputedStyle(content).overflowY : null,
+      };
+    });
+
+    expect(arrangement.direction).toBe('row');
+    expect(arrangement.contentOverflow).toBe('auto');
+  });
+});
+
+/** Albums → the second card, which navigates to the album page. */
+async function openFirstAlbum(app: Page): Promise<void> {
+  // Below 600px the sidebar is gone; the tab bar is the navigation.
+  await app.getByTestId('tab-albums').click();
+  await expect(app.getByTestId('main-content')).toHaveAttribute(
+    'data-active-view',
+    'albums',
+  );
+
+  await expect.poll(() => cardCount(app)).toBeGreaterThan(1);
+
+  // Dispatched rather than clicked: the card lives in a virtualizer
+  // inside a shadow root, and Enter expands the dropdown instead.
+  await app.evaluate(() => {
+    document
+      .querySelector('cover-grid')
+      ?.shadowRoot?.querySelectorAll('.album-card')[1]
+      ?.dispatchEvent(
+        new MouseEvent('click', { bubbles: true, composed: true }),
+      );
+  });
+
+  await expect(app.getByTestId('main-content')).toHaveAttribute(
+    'data-active-view',
+    'explore-album-details',
+  );
+  await expect(
+    details(app).locator('[data-testid="album-play"]'),
+  ).toBeVisible();
+}
+
+async function cardCount(app: Page): Promise<number> {
+  return app.evaluate(
+    () =>
+      document
+        .querySelector('cover-grid')
+        ?.shadowRoot?.querySelectorAll('.album-card').length ?? 0,
+  );
+}

e2e/specs/phone-entity-links.spec.ts

@@ -0,0 +1,135 @@
+import {
+  test,
+  expect,
+  callBinding,
+  openTheQueue,
+  NO_QUEUE_SOURCE,
+} from '../support/fixtures.js';
+import type { Page } from '@playwright/test';
+
+/**
+ * #67 — a name is not a link on a phone, and the menu is where it went.
+ *
+ * The queue panel is the surface this is visible on: its rows draw a
+ * track title and an artist credit as `explore-link`s at every width,
+ * unlike `track-list`, whose phone column set stacks title over artist
+ * as plain text already.
+ *
+ * **The pair is what makes either assertion mean anything.** A link
+ * that is gone and a menu item that never arrived is not a smaller
+ * affordance — it is a destination the phone cannot reach, which is
+ * what plan 018's "no action is unreachable at any supported size"
+ * refuses. So each test asserts the phone and the desktop in the same
+ * breath: text *and* an item here, a link *and* no item there.
+ *
+ * The desktop half is also the regression guard for the change: menus
+ * above the breakpoint must be exactly what they were, because the name
+ * beside them is still a link and a menu that repeats the row is
+ * furniture.
+ */
+
+/** The reference device's real viewport, not a resized desktop. */
+const DEVICE = { width: 424, height: 439 };
+
+/** Wide enough that the queue is a column beside the content. */
+const DESKTOP = { width: 1280, height: 800 };
+
+const row = (app: Page, index: number) =>
+  app.locator(`queue-panel .track-item[data-index="${index}"]`);
+
+/** The queue panel's own context menu, as a list of item labels. */
+async function menuLabels(app: Page): Promise<string[]> {
+  return app.evaluate(() =>
+    [
+      ...document
+        .querySelector('queue-panel')!
+        .shadowRoot!.querySelectorAll('wa-dropdown-item'),
+    ].map((item) => item.textContent?.replace(/\s+/g, ' ').trim() ?? ''),
+  );
+}
+
+/**
+ * Queue three tracks that have an album, for the reason
+ * `queue-selection.spec.ts` states at length: `explore-link` routes a
+ * title to its *album's* page and renders plain text where it cannot
+ * route, so a track with no album answers this file's question with
+ * the wrong "no link".
+ */
+async function queueThree(app: Page): Promise<void> {
+  const paths = await app.evaluate(async () => {
+    const tracks = (await window.__yjEvents.call(
+      'library.Library.GetTracks',
+      [0],
+      10_000,
+    )) as { FilePath: string; Album: string; ArtistName: string }[];
+
+    return tracks
+      .filter((t) => t.Album !== '' && t.ArtistName !== '')
+      .slice(0, 3)
+      .map((t) => t.FilePath);
+  });
+
+  await callBinding(app, 'queue.Queue.SetQueue', [
+    paths,
+    0,
+    false,
+    NO_QUEUE_SOURCE,
+  ]);
+}
+
+/** Open the row's context menu and read the items back. */
+async function openRowMenu(app: Page, index: number): Promise<string[]> {
+  await row(app, index).click({ button: 'right' });
+  await expect
+    .poll(async () => (await menuLabels(app)).length)
+    .toBeGreaterThan(0);
+
+  return menuLabels(app);
+}
+
+test.describe('an inline name and the menu that replaces it', () => {
+  test.afterEach(async ({ app }) => {
+    await app.keyboard.press('Escape');
+    await callBinding(app, 'queue.Queue.Clear').catch(() => {
+      /* an empty queue is the state we were asking for */
+    });
+    await app.setViewportSize(DESKTOP);
+  });
+
+  test('a queue row is plain text on a phone and carries the destination', async ({
+    app,
+  }) => {
+    await app.setViewportSize(DEVICE);
+    await queueThree(app);
+    await openTheQueue(app);
+    await expect(row(app, 0)).toBeVisible();
+
+    // The name is text: nothing in the row is a link at all.
+    await expect(app.locator('queue-panel .track-item .explore-link')).toHaveCount(
+      0,
+    );
+
+    const labels = await openRowMenu(app, 0);
+
+    expect(labels).toContain('Go to Artist');
+    expect(labels).toContain('Go to Album');
+  });
+
+  test('the same row on a desktop is a link, and its menu is untouched', async ({
+    app,
+  }) => {
+    await app.setViewportSize(DESKTOP);
+    await queueThree(app);
+    await openTheQueue(app);
+    await expect(row(app, 0)).toBeVisible();
+
+    await expect(
+      row(app, 0).locator('.track-title .explore-link'),
+    ).toHaveCount(1);
+
+    const labels = await openRowMenu(app, 0);
+
+    expect(labels).not.toContain('Go to Artist');
+    expect(labels).not.toContain('Go to Album');
+  });
+});

e2e/specs/phone-now-playing.spec.ts

@@ -0,0 +1,283 @@
+import { test, expect } from '../support/fixtures.js';
+
+/**
+ * Now Playing on a short screen (#51).
+ *
+ * #51 asks for a layout that "survives" ~424x439 with the controls
+ * never scrolling off. #172 measured why it did not — the stacked
+ * layout's budget is fixed, so the art gets whatever is left, and that
+ * was 39px before #64 and 53px after it.
+ *
+ * **Two separate claims are asserted here, and only one of them is
+ * about the phone.**
+ *
+ * The first is that the art is *square*. It was not: `aspect-ratio` is
+ * specified not to re-derive the width when `max-height` clamps the
+ * height, so the art was drawn as a letterbox band and `object-fit:
+ * cover` cropped the cover to it — 264x53 on the reference device. The
+ * leftover only exceeds the width above ~843px of viewport, so this
+ * was every height from ~500 to ~843 as well: most phones, and any
+ * short window. That is ordinary CSS rather than a Chrome 113 quirk,
+ * so this tier can see it, and the heights below are chosen to cover
+ * the range rather than the one device.
+ *
+ * The second is the reflow: below 500px the art and the names sit side
+ * by side, which is what takes the art from 53px to 143px. That is
+ * asserted as a *relation between boxes* — the art beside the names,
+ * not above them — because the pixel count is a consequence of the
+ * arrangement and would pin this file to one device's chrome.
+ *
+ * **What this tier cannot see** is the device's engine: CI's Chromium
+ * and WebKit are current, and #60's clipping showed what that costs.
+ * Nothing here depends on Chrome 113 behaviour — the sizing rules were
+ * checked against the device itself, at column heights of 288, 300,
+ * 451, 600 and 800, and the numbers are on #51.
+ */
+type Page = import('@playwright/test').Page;
+
+/** The reference device's real viewport. */
+const DEVICE = { width: 424, height: 439 };
+
+/**
+ * A tall phone, above the reflow's 500px. Roughly a Pixel 7, which is
+ * #51's other named device and was not attached — so what is checked
+ * here is the layout it *should* get, not that device.
+ */
+const TALL_PHONE = { width: 412, height: 869 };
+
+/** Inside the crop's old range and above the reflow: a short window. */
+const SHORT_WINDOW = { width: 390, height: 700 };
+
+/**
+ * The height the layout reflows at. Written down once here because the
+ * specs have to know which arrangement to *wait* for, not only which
+ * to assert.
+ */
+const REFLOW_AT = 500;
+
+/** Put a track in the player, so the view has art and names to lay out. */
+async function stageATrack(page: Page): Promise<void> {
+  await page.evaluate(async () => {
+    const tracks = (await window.__yjEvents.call(
+      'library.Library.GetTracks',
+      [0],
+      10_000,
+    )) as { FilePath: string }[];
+
+    await window.__yjEvents.call(
+      'queue.Queue.SetQueue',
+      [tracks.slice(0, 4).map((t) => t.FilePath), 0, false, { type: '', id: 0, label: '' }],
+      10_000,
+    );
+  });
+}
+
+/** Open the full-screen view and wait for the shell to say so. */
+async function openNowPlaying(page: Page): Promise<void> {
+  await page.evaluate(() => {
+    document.dispatchEvent(
+      new CustomEvent('navigate', {
+        detail: { view: 'now-playing' },
+        bubbles: true,
+      }),
+    );
+  });
+
+  await expect(page.getByTestId('main-content')).toHaveAttribute(
+    'data-active-view',
+    'now-playing',
+  );
+
+  // The attribute is the shell's bookkeeping and lands before the view
+  // has a track, so measuring on it alone races the first layout --
+  // which showed up as a 60x5 art on the first spec of a cold run.
+  //
+  // Waiting for a non-zero box is not enough on its own either: a
+  // previous test leaves the *other* arrangement on screen, and a
+  // stale column satisfies "has a size" perfectly. So the wait is for
+  // the arrangement this viewport should have, which is the thing
+  // every assertion below depends on. Found by this file passing one
+  // test at a time and failing in file order.
+  const wantRow = (page.viewportSize()?.height ?? 0) <= REFLOW_AT;
+
+  await page.waitForFunction(
+    (row: boolean) => {
+      const v = document.querySelector('now-playing-view');
+      const stack = v?.shadowRoot?.querySelector('.stack');
+      const el = v?.shadowRoot?.querySelector('.art img, .art .placeholder');
+      const t = v?.shadowRoot?.querySelector('.transport');
+
+      if (!el || !t) return false;
+
+      // A build with no `.stack` at all is the one before this change,
+      // and the squareness assertions are still meaningful against it
+      // -- so this waits for the arrangement only where there is one to
+      // wait for. Otherwise reverting the component to check that these
+      // tests bite produces eight timeouts instead of the measurements
+      // that make the case.
+      if (stack) {
+        const dir = getComputedStyle(stack).flexDirection;
+
+        if (dir !== (row ? 'row' : 'column')) return false;
+      }
+
+      const r = el.getBoundingClientRect();
+
+      return r.width > 0 && r.height > 0 && t.getBoundingClientRect().height > 0;
+    },
+    wantRow,
+  );
+}
+
+/**
+ * The boxes this file reasons about, read in one evaluate.
+ *
+ * It reaches into the view's shadow root rather than using locators
+ * because the question is geometric — where these boxes are *relative
+ * to each other* — and a testid per edge would be four locators and
+ * four round trips to say one thing.
+ */
+async function boxes(page: Page) {
+  return page.evaluate(() => {
+    const v = document.querySelector('now-playing-view');
+
+    if (!v || !v.shadowRoot) return null;
+
+    const rect = (sel: string) => {
+      const el = v.shadowRoot!.querySelector(sel);
+
+      if (!el) return null;
+
+      const r = el.getBoundingClientRect();
+
+      return {
+        left: r.left, right: r.right, top: r.top, bottom: r.bottom,
+        width: r.width, height: r.height,
+      };
+    };
+
+    return {
+      // Whichever of the two the track has; both carry the sizing.
+      art: rect('.art img') ?? rect('.art .placeholder'),
+      artBox: rect('.art'),
+      stack: rect('.stack'),
+      meta: rect('.meta'),
+      transport: rect('.transport'),
+      scrollHeight: v.scrollHeight,
+      clientHeight: v.clientHeight,
+    };
+  });
+}
+
+test.describe('Now Playing survives a short screen', () => {
+  test.beforeEach(async ({ app }) => {
+    await stageATrack(app);
+  });
+
+  /**
+   * The crop, at four heights spanning the range it covered. This is
+   * the assertion that fails on the build before this change: at
+   * 424x439 the art measured 264x53.
+   */
+  for (const vp of [DEVICE, SHORT_WINDOW, TALL_PHONE, { width: 900, height: 500 }]) {
+    test(`draws the art square at ${vp.width}x${vp.height}`, async ({ app }) => {
+      await app.setViewportSize(vp);
+      await openNowPlaying(app);
+
+      const b = await boxes(app);
+
+      expect(b, 'now-playing-view did not mount').not.toBeNull();
+      expect(b!.art, 'neither art nor placeholder rendered').not.toBeNull();
+
+      const { width, height } = b!.art!;
+
+      expect(width, 'the art has no width').toBeGreaterThan(0);
+      // One pixel of slack for sub-pixel layout, and no more: the
+      // defect this guards was a 5:1 band.
+      expect(
+        Math.abs(width - height),
+        `art is ${Math.round(width)}x${Math.round(height)}, not square`,
+      ).toBeLessThanOrEqual(1);
+    });
+  }
+
+  /**
+   * The promise #51 states and plan 018's matrix repeats. A floor on
+   * the art with the block scrolling was the other option on #172 and
+   * this is why it was not taken.
+   */
+  test('never scrolls the transport off the bottom', async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await openNowPlaying(app);
+
+    const b = await boxes(app);
+
+    expect(b!.transport!.bottom).toBeLessThanOrEqual(DEVICE.height);
+    expect(
+      b!.scrollHeight,
+      'the view scrolls, so the transport can be moved off screen',
+    ).toBeLessThanOrEqual(b!.clientHeight + 1);
+  });
+
+  /**
+   * The reflow itself, as a relation rather than a measurement: below
+   * 500px the names are *beside* the art, above it they are below.
+   */
+  test('puts the names beside the art below 500px', async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await openNowPlaying(app);
+
+    const b = await boxes(app);
+
+    expect(
+      b!.meta!.left,
+      'the names are not to the right of the art',
+    ).toBeGreaterThanOrEqual(b!.artBox!.right - 1);
+  });
+
+  test('keeps the names below the art on a tall phone', async ({ app }) => {
+    await app.setViewportSize(TALL_PHONE);
+    await openNowPlaying(app);
+
+    const b = await boxes(app);
+
+    expect(
+      b!.meta!.top,
+      'the names are not below the art',
+    ).toBeGreaterThanOrEqual(b!.artBox!.bottom - 1);
+  });
+
+  /**
+   * What the reflow actually does, stated as a mechanism rather than
+   * as a number: in a row the art is bounded by the row's *height*,
+   * so it fills it — where in a column it is the leftover after the
+   * names, which is what made it 53px.
+   *
+   * **The pixel count is deliberately not asserted here.** Two drafts
+   * tried. The first compared the art against the column's leftover
+   * computed from the boxes on screen and passed on the broken build,
+   * because the subtraction goes negative when the names are taller
+   * than the art — precisely the defect. The second put a floor of
+   * 100px on it, passed locally at 114 and **failed in CI at 64**: this
+   * app is long-lived, so a job staged by an earlier spec is still on
+   * screen, and the volume control renders here where it does not on
+   * Android. Both are chrome above and below this view, and both move
+   * the leftover. A test that asserts how much room CI happened to
+   * have is a test about the runner.
+   *
+   * The device numbers — 53px to 143px — are on #51, measured there,
+   * which is the only tier that can honestly produce them.
+   */
+  test('fills the row with the art rather than the leftover', async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await openNowPlaying(app);
+
+    const b = await boxes(app);
+
+    expect(b!.stack, 'there is no row to fill').not.toBeNull();
+    expect(
+      Math.abs(b!.artBox!.height - b!.stack!.height),
+      'the art does not fill the row, so it is still a leftover',
+    ).toBeLessThanOrEqual(1);
+  });
+});

e2e/specs/phone-progress-line.spec.ts

@@ -0,0 +1,136 @@
+import {
+  test,
+  expect,
+  callBinding,
+  resetEvents,
+  waitForEvent,
+  LONG_TRACK,
+  NO_QUEUE_SOURCE,
+} from '../support/fixtures.js';
+import type { Page } from '@playwright/test';
+
+/**
+ * The phone's progress line (#58).
+ *
+ * The component tier already pins what the line *says* — that it
+ * renders the backend's reported position and never a count of its own.
+ * What only a real shell can answer is **where it is**: the issue asks
+ * for a line on the border between the mini player and the tab bar, and
+ * "on the border" is two adjacencies in a grid that no component-level
+ * render has around it.
+ *
+ * It also asserts the line is not there on a desktop, which is the
+ * other half of the same fact: above 600px there is no tab bar for it
+ * to sit on the border of, and the bar carries a real seek bar.
+ */
+type Rect = { x: number; y: number; width: number; height: number };
+
+/** The reference device's real viewport. */
+const DEVICE = { width: 424, height: 439 };
+const DESKTOP = { width: 1280, height: 800 };
+
+async function rectOf(app: Page, selector: string): Promise<Rect | null> {
+  return app.evaluate((sel) => {
+    const el = document.querySelector(sel);
+
+    if (!el) return null;
+
+    const r = el.getBoundingClientRect();
+
+    return { x: r.x, y: r.y, width: r.width, height: r.height };
+  }, selector);
+}
+
+/**
+ * Put the 90-second fixture on and wait for the first position report.
+ *
+ * The long track rather than any track: every other fixture is 2-6
+ * seconds, which is shorter than the time this spec takes to measure
+ * three rectangles.
+ */
+async function play(app: Page): Promise<void> {
+  const tracks = await callBinding<{ FilePath: string; TrackName: string }[]>(
+    app,
+    'library.Library.GetTracks',
+    [0],
+  );
+
+  // `TrackName`, not `Title`: that is what the library model calls it.
+  const long = tracks.find((t) => t.TrackName === LONG_TRACK);
+
+  expect(long, `no fixture track named ${LONG_TRACK}`).toBeTruthy();
+
+  await callBinding(app, 'queue.Queue.Clear');
+  await resetEvents(app);
+  await callBinding(app, 'queue.Queue.SetQueue', [
+    [long!.FilePath],
+    0,
+    false,
+    NO_QUEUE_SOURCE,
+  ]);
+  await waitForEvent(app, 'QueueChanged');
+  await callBinding(app, 'queue.Queue.Play');
+  await waitForEvent(app, 'PlaybackPositionChanged', { timeoutMs: 15_000 });
+}
+
+test.describe('the progress line sits on the border between the bars', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await play(app);
+  });
+
+  /*
+   * Every test here starts a LONG_TRACK and the suite is workers: 1,
+   * fullyParallel: false against one long-lived app — so without this
+   * the four phone-* specs that follow alphabetically inherit a playing
+   * queue. phone-transport.spec.ts records where that lesson came from:
+   * the fault first showed up as a flake in a spec about something else.
+   */
+  test.afterEach(async ({ app }) => {
+    await callBinding(app, 'queue.Queue.Clear').catch(() => {
+      /* already empty */
+    });
+    await app.setViewportSize(DESKTOP);
+  });
+
+  test('spans the width, between the mini player and the tab bar', async ({
+    app,
+  }) => {
+    const line = await rectOf(app, 'player-progress-line');
+    const bar = await rectOf(app, '.bottom-bar');
+    const nav = await rectOf(app, 'bottom-nav');
+
+    expect(line, 'no progress line on the phone').not.toBeNull();
+    expect(bar).not.toBeNull();
+    expect(nav).not.toBeNull();
+
+    // A border, not a band: 2px, the full width, and touching both.
+    expect(line!.height).toBeCloseTo(2, 0);
+    expect(line!.width).toBeCloseTo(bar!.width, 0);
+    expect(line!.y).toBeCloseTo(bar!.y + bar!.height, 0);
+    expect(nav!.y).toBeCloseTo(line!.y + line!.height, 0);
+  });
+
+  /**
+   * It is 2px on the top edge of the tab bar, which is exactly where a
+   * thumb aiming at a tab lands. A line that sometimes seeks is worse
+   * than one that never does, so it must take no part in hit testing
+   * at all.
+   */
+  test('takes no taps', async ({ app }) => {
+    const line = await rectOf(app, 'player-progress-line');
+
+    const hit = await app.evaluate(
+      ({ x, y }) => document.elementFromPoint(x, y)?.tagName ?? '',
+      { x: line!.x + line!.width / 2, y: line!.y + 1 },
+    );
+
+    expect(hit).not.toBe('PLAYER-PROGRESS-LINE');
+  });
+
+  test('is not there on a desktop', async ({ app }) => {
+    await app.setViewportSize(DESKTOP);
+
+    await expect(app.locator('player-progress-line')).toBeHidden();
+  });
+});

e2e/specs/phone-shell.spec.ts

@@ -98,6 +98,58 @@ test.describe('the shell on a phone', () => {
     ).toBeVisible();
   });
 
+  test('draws "More" as a sheet on the bottom edge (#71)', async ({ app }) => {
+    await app.getByTestId('tab-more').click();
+    await expect(app.getByTestId('nav-drawer').locator('app-sidebar'))
+      .toBeVisible();
+
+    // What the report is about is geometry, and geometry is what no
+    // other assertion here can see: the side drawer was a 200px column
+    // opening away from the thumb that asked for it, with the rest of
+    // its 400px band empty. Measured rather than screenshotted, since
+    // the failure is a number.
+    //
+    // Polled, because a sheet *arrives*: the drawer's show animation
+    // translates it a full height below the fold, so a measurement
+    // taken the moment its content is visible reports a box hanging
+    // 412px off the bottom of the screen. Asking for the settled
+    // number is the assertion; asking once is a race.
+    const measure = () => app.evaluate(() => {
+      const nav = document.querySelector('bottom-nav');
+      const drawer = nav?.shadowRoot?.querySelector('wa-drawer');
+      const dialog = drawer?.shadowRoot?.querySelector('[part~="dialog"]');
+      const sidebar = nav?.shadowRoot?.querySelector('app-sidebar');
+      const row = sidebar?.shadowRoot?.querySelector('li button');
+      const box = dialog?.getBoundingClientRect();
+
+      return {
+        left: Math.round(box?.left ?? -1),
+        right: Math.round(box?.right ?? -1),
+        bottom: Math.round(box?.bottom ?? -1),
+        height: Math.round(box?.height ?? -1),
+        row: Math.round(row?.getBoundingClientRect().height ?? -1),
+        viewport: [window.innerWidth, window.innerHeight],
+      };
+    });
+
+    await expect
+      .poll(async () => (await measure()).bottom)
+      .toBe(PHONE.height);
+
+    const sheet = await measure();
+
+    expect(sheet.left).toBe(0);
+    expect(sheet.right).toBe(sheet.viewport[0]);
+
+    // A surface covering the whole screen is a page, not a sheet --
+    // which is also what leaves an outside to tap on, the only pointer
+    // route out of it (#171 is the same question one surface over).
+    expect(sheet.height).toBeLessThan(sheet.viewport[1]);
+
+    // 48px rows, from #186's touch floor and #60's context sheet.
+    expect(sheet.row).toBeGreaterThanOrEqual(48);
+  });
+
   for (const vp of [PHONE, SMALL_PHONE]) {
     test(`does not scroll sideways at ${vp.width}×${vp.height}`, async ({ app }) => {
       await app.setViewportSize(vp);
@@ -130,6 +182,25 @@ test.describe('the shell on a phone', () => {
     // are here, and they are the *same* components -- this view
     // composes the transport rather than reimplementing it.
     await expect(app.locator('now-playing-view seek-bar')).toBeVisible();
+
+    // Volume is here **because the player says there is one** (#64),
+    // not because this is a phone. This tier is the platform that owns
+    // its own volume, so what it can assert is that the control's
+    // presence follows that answer -- an inverted polarity in
+    // `volume-style-store` fails here and in `bottom-bar.spec.ts`, and
+    // the *absent* branch is checked in the component tier, where the
+    // binding can be stubbed. Nothing here can reach the Android side.
+    const systemOwns = await app.evaluate(
+      async () =>
+        (await window.__yjEvents.call(
+          'player.Player.SystemOwnsVolume',
+          [],
+          5_000,
+        )) as boolean,
+    );
+
+    expect(systemOwns, 'this platform should own its own volume').toBe(false);
+
     await expect(app.locator('now-playing-view volume-control')).toBeVisible();
 
     // Back goes where the user came from, through the nav stack.

e2e/specs/phone-transport.spec.ts

@@ -0,0 +1,315 @@
+import { test, expect } from '../support/fixtures.js';
+
+/**
+ * The phone's transport (#59, #56).
+ *
+ * #56 reports that "the playback controls are the most important thing
+ * in the mobile app and they are tiny". Measured at the reference
+ * device's 424x439 before this, every one of them was **33x21px**, and
+ * the favourite beside them — which #59 keeps on the bar — was
+ * **18x14px**, the smallest control in the app.
+ *
+ * #59 is what makes the sizes affordable: five controls plus a queue
+ * button at 44px does not fit 424 CSS px, so the bar carries three and
+ * the rest are on the full-screen view.
+ *
+ * **The assertion that matters is not the pixel count.** Plan 018's
+ * matrix promises that *no action is ever unreachable at any supported
+ * size*, and #59 removes three controls from the phone's bar — so the
+ * first thing this file checks is that all three are still reachable,
+ * by walking the route a user would. A spec that only measured the
+ * survivors would be green on a build that had made shuffle
+ * unreachable, which is the failure mode this pair of issues is one
+ * mistake away from.
+ */
+type Page = import('@playwright/test').Page;
+
+/** The reference device's real viewport. */
+const DEVICE = { width: 424, height: 439 };
+const PHONE = { width: 390, height: 780 };
+const DESKTOP = { width: 1280, height: 800 };
+
+/**
+ * The touch-target floor. 44px is what #56's Findings name and what
+ * #55's queue header was sized to, so the app has one number.
+ */
+const TARGET = 44;
+
+/** The play button is named for its action, not its identity. */
+const PLAY_PAUSE = /^(Play|Pause)$/;
+
+const barControls = (page: Page) =>
+  page.locator('audio-player player-controls');
+
+/**
+ * `name` may be a regex, and for play/pause it must be: that button is
+ * named for the *action*, so it is "Pause" while a track runs and
+ * "Play" when it stops. An exact 'Play' made these tests wait out a
+ * fixture track (11.1s each, passing by luck) and would have failed
+ * outright against `LONG_TRACK`. A test about a control's size does not
+ * care what the transport is doing.
+ */
+async function sizeOf(
+  page: Page,
+  name: string | RegExp,
+): Promise<[number, number]> {
+  const box = await page
+    .getByRole('button', { name, exact: typeof name === 'string' })
+    .boundingBox();
+
+  expect(box, `no button named ${name}`).not.toBeNull();
+
+  return [box!.width, box!.height];
+}
+
+/** Put something in the queue, so the transport has a track to act on. */
+async function stageATrack(page: Page): Promise<void> {
+  await page.evaluate(async () => {
+    const tracks = (await window.__yjEvents.call(
+      'library.Library.GetTracks',
+      [0],
+      10_000,
+    )) as { FilePath: string }[];
+
+    await window.__yjEvents.call(
+      'queue.Queue.SetQueue',
+      [tracks.slice(0, 4).map((t) => t.FilePath), 0, false, { type: '', id: 0, label: '' }],
+      10_000,
+    );
+  });
+}
+
+test.describe('the phone bar carries three controls', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await stageATrack(app);
+  });
+
+  test('drops shuffle, repeat and the queue from the bar', async ({ app }) => {
+    const bar = barControls(app);
+
+    await expect(bar.getByRole('button', { name: 'Previous track' })).toBeVisible();
+    await expect(bar.getByRole('button', { name: 'Next track' })).toBeVisible();
+
+    // Not in the bar's own subtree. Asserted against the bar rather
+    // than the page, because the whole point is that they moved rather
+    // than went away -- a page-wide `not.toBeVisible()` would fail the
+    // moment Now Playing is open and would be asserting the wrong
+    // thing besides.
+    await expect(bar.getByRole('button', { name: 'Shuffle' })).toHaveCount(0);
+    await expect(bar.getByRole('button', { name: /^Repeat/ })).toHaveCount(0);
+    await expect(app.locator('#queue-button')).toBeHidden();
+  });
+
+  /**
+   * The promise, walked. Every control #59 takes off the bar is
+   * reachable from the mini player's art in one tap.
+   */
+  test('leaves every removed control reachable from Now Playing', async ({
+    app,
+  }) => {
+    await app.getByTestId('open-now-playing').click();
+
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'now-playing',
+    );
+
+    await expect(app.getByRole('button', { name: 'Shuffle' })).toBeVisible();
+    await expect(app.getByRole('button', { name: /^Repeat/ })).toBeVisible();
+    await expect(app.getByRole('button', { name: 'Show the queue' })).toBeVisible();
+  });
+
+  test('sizes what is left for a thumb', async ({ app }) => {
+    for (const name of ['Previous track', 'Next track']) {
+      const [w, h] = await sizeOf(app, name);
+
+      expect(w, `${name} width`).toBeGreaterThanOrEqual(TARGET);
+      expect(h, `${name} height`).toBeGreaterThanOrEqual(TARGET);
+    }
+
+    // Play is deliberately bigger than its neighbours: a row of
+    // identical squares says every action is equally likely, which is
+    // not true of play.
+    const [pw, ph] = await sizeOf(app, PLAY_PAUSE);
+    const [nw] = await sizeOf(app, 'Next track');
+
+    expect(ph).toBeGreaterThanOrEqual(TARGET);
+    expect(pw).toBeGreaterThan(nw);
+  });
+
+  /**
+   * The favourite was 18x14 and is one of the three controls #59
+   * keeps, so it is part of this issue rather than a nicety.
+   */
+  test('sizes the favourite, which was the smallest control in the app', async ({
+    app,
+  }) => {
+    const fav = app
+      .locator('now-playing')
+      .getByRole('button', { name: /Favorites$/ });
+
+    const box = await fav.boundingBox();
+
+    expect(box).not.toBeNull();
+    expect(box!.width).toBeGreaterThanOrEqual(TARGET);
+    expect(box!.height).toBeGreaterThanOrEqual(TARGET);
+  });
+
+  /**
+   * **The route to the queue must not depend on what is playing.**
+   *
+   * `now-playing` renders two branches, and the no-track one had no
+   * `.expand` button on its placeholder — so with nothing loaded there
+   * was no way to Now Playing, and once #59 takes the queue button off
+   * the bar that makes the *queue* unreachable. The queue is persisted
+   * across restarts, so "tracks queued, nothing playing" is a state the
+   * app launches into.
+   *
+   * This is asserted with the queue explicitly emptied rather than by
+   * relying on the app not having played anything: `make e2e` runs one
+   * long-lived app across every spec file (#168), so "no track loaded"
+   * is otherwise whatever the file before this one left behind — which
+   * is how the underlying fault first showed up as a flake in a spec
+   * about something else.
+   */
+  test('reaches the queue with nothing playing', async ({ app }) => {
+    await app.evaluate(async () => {
+      await window.__yjEvents.call('queue.Queue.Clear', [], 10_000);
+    });
+
+    await expect(app.getByTestId('open-now-playing')).toBeVisible();
+
+    await app.getByTestId('open-now-playing').click();
+    await app.getByTestId('npv-queue').click();
+
+    await expect(app.locator('#queue-panel')).toHaveAttribute('open', '');
+  });
+
+  test('still fits, with nothing to scroll sideways to', async ({ app }) => {
+    const fit = await app.evaluate(() => ({
+      scroll: document.body.scrollWidth,
+      client: document.body.clientWidth,
+    }));
+
+    expect(fit.scroll).toBe(fit.client);
+  });
+});
+
+test.describe('the full-screen transport is the page', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DEVICE);
+    await stageATrack(app);
+    await app.getByTestId('open-now-playing').click();
+  });
+
+  test('draws all five, larger than the bar draws any', async ({ app }) => {
+    const [pw, ph] = await sizeOf(app, PLAY_PAUSE);
+
+    expect(pw).toBeGreaterThanOrEqual(56);
+    expect(ph).toBeGreaterThanOrEqual(56);
+
+    for (const name of ['Shuffle', 'Previous track', 'Next track']) {
+      const [w, h] = await sizeOf(app, name);
+
+      expect(w, `${name} width`).toBeGreaterThanOrEqual(TARGET);
+      expect(h, `${name} height`).toBeGreaterThanOrEqual(TARGET);
+    }
+  });
+
+  test('fits at both phone widths', async ({ app }) => {
+    for (const size of [DEVICE, PHONE]) {
+      await app.setViewportSize(size);
+
+      const fit = await app.evaluate(() => ({
+        scroll: document.body.scrollWidth,
+        client: document.body.clientWidth,
+      }));
+
+      expect(fit.scroll, `${size.width}px`).toBe(fit.client);
+    }
+  });
+});
+
+/**
+ * **The desktop bar is not what either issue is about, and must not
+ * move.** Both are `Platform/Android`; this is the guard that says so
+ * in a way a build can check.
+ *
+ * It caught a real regression while it was being written: a generic
+ * `font-size` on the buttons took them from the UA stylesheet's 13.3px
+ * to the shell's 16px and grew every one from 33x21 to 36x24 — a
+ * change nobody asked for, invisible to every other assertion here.
+ */
+test.describe('the desktop bar is untouched', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(DESKTOP);
+    await stageATrack(app);
+  });
+
+  test('keeps all five controls and the queue button', async ({ app }) => {
+    const bar = barControls(app);
+
+    for (const name of ['Shuffle', 'Previous track', 'Next track']) {
+      await expect(bar.getByRole('button', { name })).toBeVisible();
+    }
+
+    await expect(bar.getByRole('button', { name: /^Repeat/ })).toBeVisible();
+    await expect(app.locator('#queue-button')).toBeVisible();
+  });
+
+  /**
+   * **The mechanism, because the pixels are the engine's.**
+   *
+   * The first version of this asserted the literal `'33x21'`, measured
+   * on `main` in Chromium — and WebKit draws the same button **36x24**,
+   * so it failed in CI on a build where nothing was wrong. A button's
+   * box comes from the UA stylesheet when the author sets nothing, and
+   * what each UA sets is its own business.
+   *
+   * What this PR must not do is *set* anything here, so that is what is
+   * asserted: our two box properties are unset, and the font is still
+   * the UA's rather than the shell's. That is precisely the regression
+   * this caught the first time — a generic `font-size: inherit` took
+   * these from the UA's default to 16px — and it catches it in either
+   * engine.
+   */
+  test('sets no size of its own on the desktop bar', async ({ app }) => {
+    const measured = await barControls(app).evaluate((el) => {
+      // A bare button with no author styles: whatever this engine
+      // gives one is what the bar's buttons must still be.
+      const probe = document.createElement('button');
+
+      document.body.appendChild(probe);
+
+      const uaFontSize = getComputedStyle(probe).fontSize;
+
+      probe.remove();
+
+      return [...el.shadowRoot!.querySelectorAll('button')].map((b) => {
+        const cs = getComputedStyle(b);
+        const r = b.getBoundingClientRect();
+
+        return {
+          minWidth: cs.minWidth,
+          minHeight: cs.minHeight,
+          usesUaFont: cs.fontSize === uaFontSize,
+          size: `${Math.round(r.width)}x${Math.round(r.height)}`,
+        };
+      });
+    });
+
+    expect(measured).toHaveLength(5);
+
+    for (const m of measured) {
+      expect(m.minWidth, 'min-width').toBe('0px');
+      expect(m.minHeight, 'min-height').toBe('0px');
+      expect(m.usesUaFont, 'font-size is still the UA default').toBe(true);
+    }
+
+    // And all five are the same box: `.play` takes a larger size in
+    // both sized contexts, so this is what says the desktop is neither
+    // of them.
+    expect(new Set(measured.map((m) => m.size)).size).toBe(1);
+  });
+});

e2e/specs/queue-as-a-screen.spec.ts

@@ -1,4 +1,4 @@
-import { test, expect } from '../support/fixtures.js';
+import { test, expect, openTheQueue } from '../support/fixtures.js';
 
 /**
  * #55 — the queue is a *place* while it covers the content, and a
@@ -37,15 +37,37 @@ const DEVICE = { width: 424, height: 439 };
 /** Wide enough that the queue is a column: 1280 − 200 − 320 ≥ 480. */
 const DESKTOP = { width: 1280, height: 800 };
 
+/**
+ * The Compact band, where the queue is a *screen* (644 − 320 < 480) and
+ * the bottom bar still carries its button.
+ *
+ * Two of these tests need both facts at once and only this band has
+ * them: below 600px #59 takes the button off the bar, so there is no
+ * toggle to re-press and the queue is opened from Now Playing — which
+ * is itself a detail view, so "the destination stays lit" is vacuously
+ * true there rather than tested.
+ */
+const COMPACT = { width: 700, height: 600 };
+
 const activeView = (page: Page) => page.getByTestId('main-content');
 const queue = (page: Page) => page.locator('#queue-panel');
 const toggle = (page: Page) => page.locator('#queue-button');
 
+/**
+ * Whether the queue is up.
+ *
+ * The panel's own attribute rather than the toggle's `aria-expanded`,
+ * because below 600px there is no toggle to ask (#59) — and the panel
+ * is the one fact both of them reflect anyway.
+ */
 async function expectQueue(page: Page, open: boolean): Promise<void> {
-  await expect(toggle(page)).toHaveAttribute(
+  const panel = queue(page);
-    'aria-expanded',
+
-    String(open),
+  if (open) {
-  );
+    await expect(panel).toHaveAttribute('open', '');
+  } else {
+    await expect(panel).not.toHaveAttribute('open', '');
+  }
 }
 
 test.describe('the queue is a screen where it covers the content', () => {
@@ -55,12 +77,17 @@ test.describe('the queue is a screen where it covers the content', () => {
     await expect(activeView(app)).toHaveAttribute('data-active-view', 'albums');
   });
 
+  // On a phone the queue is opened from Now Playing (#59), so the page
+  // *underneath* it is `now-playing` and the journey is two entries
+  // deep: albums -> now-playing -> queue. That is the real route a user
+  // takes, which is why these do not reach for the shortcut.
+
   test('back closes the queue and leaves the page where it was', async ({
     app,
   }) => {
     await expect(queue(app)).toHaveAttribute('overlay', '');
 
-    await toggle(app).click();
+    await openTheQueue(app);
     await expectQueue(app, true);
 
     await app.goBack();
@@ -69,27 +96,31 @@ test.describe('the queue is a screen where it covers the content', () => {
     // The page underneath is untouched. Before #55 this was the
     // *previous* view, because the queue was not in the stack at all
     // and back spent an entry navigating something nobody could see.
-    await expect(activeView(app)).toHaveAttribute('data-active-view', 'albums');
+    await expect(activeView(app)).toHaveAttribute(
+      'data-active-view',
+      'now-playing',
+    );
   });
 
   test('costs exactly one entry, so the next press navigates', async ({
     app,
   }) => {
-    await toggle(app).click();
+    await openTheQueue(app);
     await expectQueue(app, true);
 
     await app.goBack();
     await expectQueue(app, false);
+    await expect(activeView(app)).toHaveAttribute(
+      'data-active-view',
+      'now-playing',
+    );
 
     await app.goBack();
 
-    // Whatever the launch page is, it is not Albums — the point is that
+    // Exactly one entry each: the second press leaves Now Playing for
-    // this press moved the app rather than being swallowed by a queue
+    // the page it was opened from, rather than being swallowed by a
-    // that had already closed.
+    // queue that had already closed.
-    await expect(activeView(app)).not.toHaveAttribute(
+    await expect(activeView(app)).toHaveAttribute('data-active-view', 'albums');
-      'data-active-view',
-      'albums',
-    );
   });
 
   /**
@@ -116,15 +147,9 @@ test.describe('the queue is a screen where it covers the content', () => {
         await app.keyboard.press('Escape');
       },
     ],
-    [
-      'the toggle it was opened from',
-      async (app: Page) => {
-        await toggle(app).click();
-      },
-    ],
   ] as Array<[string, (app: Page) => Promise<void>]>) {
     test(`${name} leaves no entry behind`, async ({ app }) => {
-      await toggle(app).click();
+      await openTheQueue(app);
       await expectQueue(app, true);
 
       await dismiss(app);
@@ -132,7 +157,10 @@ test.describe('the queue is a screen where it covers the content', () => {
 
       await app.goBack();
 
-      await expect(activeView(app)).not.toHaveAttribute(
+      // One press, one screen: Now Playing is what the queue was opened
+      // from, so leaving it lands on Albums. An orphaned entry would
+      // have spent this press on nothing and left it here.
+      await expect(activeView(app)).toHaveAttribute(
         'data-active-view',
         'albums',
       );
@@ -149,26 +177,14 @@ test.describe('the queue is a screen where it covers the content', () => {
    * `back-navigation.spec.ts` gives: the class was right throughout the
    * bug that rule exists for.
    */
-  test('leaves the tab it was opened from highlighted', async ({ app }) => {
-    await expect(
-      app.getByRole('button', { name: 'Albums', exact: true }),
-    ).toHaveAttribute('aria-current', 'page');
-
-    await toggle(app).click();
-    await expectQueue(app, true);
-
-    await expect(
-      app.getByRole('button', { name: 'Albums', exact: true }),
-    ).toHaveAttribute('aria-current', 'page');
-  });
 
   /**
-   * With the panel spanning the whole width the scrim has no uncovered
+   * With the panel spanning the whole width there is no scrim here at
-   * pixels, so the close button is the only pointer route out of a
+   * all (#171), so the close button is the only pointer route out of a
    * full-screen surface. Measured at 424×439 before #55: **25×21px**.
    */
   test('offers a way out a thumb can hit', async ({ app }) => {
-    await toggle(app).click();
+    await openTheQueue(app);
 
     const box = await app
       .getByRole('button', { name: 'Close queue' })
@@ -178,6 +194,33 @@ test.describe('the queue is a screen where it covers the content', () => {
     expect(box!.width).toBeGreaterThanOrEqual(44);
     expect(box!.height).toBeGreaterThanOrEqual(44);
   });
+
+  /**
+   * #171 — and it draws no scrim, because there is nowhere to tap.
+   *
+   * `.panel-content` is `width: 100%` here, so the scrim sat entirely
+   * underneath it: measured at 424×439, host, panel and scrim all
+   * 424×318. #24's tap-outside-to-close cannot exist on a surface with
+   * no outside, and a `cursor: pointer` layer nobody can reach is a
+   * claim the component cannot keep.
+   *
+   * Asserted as absence rather than by clicking, for the reason the
+   * issue gives: a naive phone case clicks the scrim's centre and hits
+   * the panel, so it passes on the build this exists to fail. The scrim
+   * is still real between 600 and 899px, which `queue-overlay.spec.ts`
+   * asserts at 900×600 by clicking it.
+   */
+  test('draws no scrim, because a screen has no outside to tap', async ({
+    app,
+  }) => {
+    await openTheQueue(app);
+
+    const scrim = await queue(app).evaluate(
+      (el) => el.shadowRoot!.querySelector('.scrim') !== null,
+    );
+
+    expect(scrim).toBe(false);
+  });
 });
 
 /**
@@ -204,7 +247,7 @@ test('the panel stays out of the paint-contained region', async ({ app }) => {
   // from it — and because the host drops `paint` from its own
   // containment deliberately in overlay mode, so a closed panel answers
   // a different question.
-  await toggle(app).click();
+  await openTheQueue(app);
   await expectQueue(app, true);
 
   const ancestry = await app.evaluate(() => {
@@ -235,6 +278,66 @@ test('the panel stays out of the paint-contained region', async ({ app }) => {
   }
 });
 
+/**
+ * Two properties need the queue to be a *screen* and the bar to still
+ * have its button, and only the Compact band has both — below 600px #59
+ * takes the button off the bar.
+ */
+test.describe('a screen opened from the bar', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(COMPACT);
+    await app.getByTestId('nav-albums').click();
+    await expect(activeView(app)).toHaveAttribute('data-active-view', 'albums');
+    await expect(queue(app)).toHaveAttribute('overlay', '');
+  });
+
+  /**
+   * A detail view leaves the destination it was opened from lit
+   * (`active-view-store`, #72), and the queue inherits that — it is
+   * published with `isPrimary: false`, so `isActive('albums')` is still
+   * true underneath it.
+   *
+   * `aria-current` rather than a class, for the reason
+   * `back-navigation.spec.ts` gives: the class was right throughout the
+   * bug that rule exists for.
+   */
+  test('leaves the destination it was opened from highlighted', async ({
+    app,
+  }) => {
+    // By testid, not by role: at 700px the sidebar is in icon mode, so
+    // what the item is *named* is a different question from which item
+    // it is. The assertion is still `aria-current`, which is the
+    // accessible fact.
+    const albums = app.getByTestId('nav-albums');
+
+    await expect(albums).toHaveAttribute('aria-current', 'page');
+
+    await toggle(app).click();
+    await expectQueue(app, true);
+
+    await expect(albums).toHaveAttribute('aria-current', 'page');
+  });
+
+  /** The toggle is a fourth way out, and it unwinds the entry like the
+   *  other three — through the panel's attribute, not its own handler. */
+  test('closes from the same toggle, leaving no entry behind', async ({
+    app,
+  }) => {
+    await toggle(app).click();
+    await expectQueue(app, true);
+
+    await toggle(app).click();
+    await expectQueue(app, false);
+
+    await app.goBack();
+
+    await expect(activeView(app)).not.toHaveAttribute(
+      'data-active-view',
+      'albums',
+    );
+  });
+});
+
 /**
  * The column is not a place. Somebody docked it; back must not undock
  * it, and navigating to another view must not take it away.

e2e/specs/queue-overlay.spec.ts

@@ -1,4 +1,4 @@
-import { test, expect } from '../support/fixtures.js';
+import { test, expect, openTheQueue } from '../support/fixtures.js';
 
 /**
  * #24 — the queue panel does not take the page's width away from it.
@@ -54,15 +54,15 @@ const shellGeometry = (page: import('@playwright/test').Page) =>
     };
   });
 
-async function openQueue(page: import('@playwright/test').Page) {
+/**
-  const toggle = page.locator('#queue-button');
+ * Opening the queue is `openTheQueue`, which takes the route this
-
+ * viewport offers. It used to be a local helper that clicked
-  if ((await toggle.getAttribute('aria-expanded')) !== 'true') {
+ * `#queue-button` unconditionally, and #59 hid that button below
-    await toggle.click();
+ * 600px -- so the two phone bands here failed on a build where the
-  }
+ * queue was working perfectly, having been asserting *how* it opens as
-
+ * much as what it does.
-  await expect(toggle).toHaveAttribute('aria-expanded', 'true');
+ */
-}
+const openQueue = openTheQueue;
 
 test.describe('an open queue leaves the content its width', () => {
   for (const band of BANDS) {

e2e/specs/touch-gestures.spec.ts

@@ -0,0 +1,311 @@
+import { test, expect, callBinding } from '../support/fixtures.js';
+
+/**
+ * The touch gestures against the real app (plan 019, #63; long-press
+ * from plan 016 B2).
+ *
+ * The component tier proves the gestures in isolation, against markup
+ * it built itself. What it cannot prove is the half that made this one
+ * document listener instead of six: that the announced gesture reaches
+ * the handler a *real* component bound — `track-list` delegates on the
+ * `lit-virtualizer` rather than binding per row — and that the real
+ * menu opens from it, a path with its own history of opening and then
+ * refusing to work (see `menu-keyboard.spec.ts`).
+ *
+ * **Both halves of the reassignment are here, and the second is the
+ * one that matters.** #63 makes a hold on a *track row* mean selection
+ * mode; every other surface in the app keeps the context menu it has
+ * had, because an unclaimed `yj-long-press` still becomes a
+ * `contextmenu`. A spec that only checked the row would pass on a
+ * build that had silently broken the other thirteen menus.
+ *
+ * The pointer events are dispatched rather than performed: this
+ * project runs Desktop Chrome and Desktop Safari, neither of which has
+ * touch. So this is honest about what it checks — the app's own
+ * listeners, on the app's own DOM, from the events a touch would
+ * produce — and not about a real finger. The finger is the Android
+ * tier, and it found something this cannot see: Chrome 113's WebView
+ * fires its own `contextmenu` on a long press, which is why the module
+ * announces the gesture from a native event rather than standing down.
+ */
+
+/** A common small phone, as in `phone-shell.spec.ts`. */
+const PHONE = { width: 390, height: 844 };
+
+/** Comfortably past the module's 500ms hold. */
+const HELD = 900;
+
+type Page = import('@playwright/test').Page;
+
+/** A component's menu panel, or null while it is not rendered. */
+const panel = (page: Page, host: string) =>
+  page.evaluate((tag) => {
+    const el = document
+      .querySelector(tag)
+      ?.shadowRoot?.querySelector('.context-menu-panel');
+
+    if (!el) return null;
+
+    return {
+      role: el.getAttribute('role'),
+      label: el.getAttribute('aria-label'),
+      items: el.querySelectorAll('[role="menuitem"]').length,
+    };
+  }, host);
+
+/** How many tracks the selection bar says are selected, or null. */
+const selectionCount = (page: Page) =>
+  page.evaluate(() => {
+    const bar = document
+      .querySelector('track-list')
+      ?.shadowRoot?.querySelector('selection-bar');
+
+    return bar ? (bar as unknown as { count: number }).count : null;
+  });
+
+/**
+ * Press an element, optionally dragging partway through — the shape of
+ * a scroll that begins on a row, which must be neither gesture — and
+ * optionally lifting, which is what makes it a tap rather than a hold.
+ */
+async function press(
+  page: Page,
+  selector: { host: string; inner: string },
+  opts: { driftY?: number; lift?: boolean } = {},
+): Promise<void> {
+  await page.evaluate(
+    ({ host, inner, drift, lift }) => {
+      const el = document
+        .querySelector(host)
+        ?.shadowRoot?.querySelector(inner);
+
+      if (!el) throw new Error(`no ${inner} in ${host} to press`);
+
+      const box = el.getBoundingClientRect();
+      const x = Math.round(box.left + box.width / 2);
+      const y = Math.round(box.top + box.height / 2);
+      const send = (type: string, dy = 0) =>
+        el.dispatchEvent(
+          new PointerEvent(type, {
+            bubbles: true,
+            composed: true,
+            cancelable: true,
+            pointerType: 'touch',
+            isPrimary: true,
+            clientX: x,
+            clientY: y + dy,
+          }),
+        );
+
+      send('pointerdown');
+
+      if (drift) send('pointermove', drift);
+      if (lift) send('pointerup');
+    },
+    {
+      host: selector.host,
+      inner: selector.inner,
+      drift: opts.driftY ?? 0,
+      lift: opts.lift ?? false,
+    },
+  );
+}
+
+// `.track-row`, not `[role="row"]`: the column header is a row too, and
+// it is the *first* one — a press on it is correctly ignored, which
+// reads exactly like the gesture not working.
+const TRACK_ROW = { host: 'track-list', inner: '.track-row' };
+
+test.describe('a hold on a track row selects it', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(PHONE);
+    await app.getByTestId('tab-tracks').click();
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'tracks',
+    );
+  });
+
+  test.afterEach(async ({ app }) => {
+    // Every other spec file runs against a desktop, and the viewport
+    // belongs to the shared context rather than to this file.
+    await app.setViewportSize({ width: 1440, height: 900 });
+  });
+
+  test('raises the selection bar rather than the context menu', async ({
+    app,
+  }) => {
+    await expect.poll(() => selectionCount(app)).toBeNull();
+
+    await press(app, TRACK_ROW);
+
+    await expect
+      .poll(() => selectionCount(app), { timeout: HELD + 2000 })
+      .toBe(1);
+
+    // The gesture is claimed, so the menu this hold used to open must
+    // not also be up -- on a phone that would be a sheet over the bar.
+    expect(await panel(app, 'track-list')).toBeNull();
+  });
+
+  test('is neither gesture when the press turns into a scroll', async ({
+    app,
+  }) => {
+    await press(app, TRACK_ROW, { driftY: 40 });
+    await app.waitForTimeout(HELD);
+
+    expect(await selectionCount(app)).toBeNull();
+    expect(await panel(app, 'track-list')).toBeNull();
+  });
+});
+
+test.describe('a hold anywhere else still opens the menu', () => {
+  test.beforeEach(async ({ app }) => {
+    await app.setViewportSize(PHONE);
+    await app.getByTestId('tab-albums').click();
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'albums',
+    );
+  });
+
+  test.afterEach(async ({ app }) => {
+    await app.setViewportSize({ width: 1440, height: 900 });
+  });
+
+  test('reaches the delegated handler and opens the real menu', async ({
+    app,
+  }) => {
+    // The property that let #63 reassign the hold without touching one
+    // of the fourteen context menus: unclaimed, it is what it was.
+    // Without this half, breaking all of them passes the suite.
+    await expect.poll(() => panel(app, 'cover-grid')).toBeNull();
+
+    await press(app, { host: 'cover-grid', inner: '[role="option"]' });
+
+    await expect
+      .poll(() => panel(app, 'cover-grid'), { timeout: HELD + 2000 })
+      .toMatchObject({ role: 'menu' });
+
+    // The same panel Shift+F10 opens, items and all -- not an empty
+    // popup that happened to become visible.
+    expect((await panel(app, 'cover-grid'))?.items).toBeGreaterThan(0);
+  });
+});
+
+/**
+ * Swipe right on a track row to queue it (plan 019 phase 2, #63).
+ *
+ * The component tier has the rule this obeys — one row is a position,
+ * several are a choice — against a queue that is a fake. What is only
+ * true here is that the gesture reaches the *real* queue: `AddTracks`
+ * is a Go method, the queue is persisted, and "the row was added"
+ * is a question only the backend can answer.
+ *
+ * **It is Chromium-only, and that is a property of the browser rather
+ * than a gap.** The gesture runs on touch events, because Chrome 113's
+ * WebView cancels the pointer stream ~16px into any drag whatever
+ * `touch-action` says. Desktop WebKit implements no `TouchEvent`
+ * constructor at all — touch events are a mobile-Safari surface — so
+ * the events this needs cannot be built there. Skipping loudly is
+ * better than a spec that quietly asserts nothing on half the matrix,
+ * which is what `layout-overflow.spec.ts` and `back-navigation.spec.ts`
+ * were each doing when they were green on a broken build.
+ */
+test.describe('a swipe right on a track row queues it', () => {
+  test.beforeEach(async ({ app, browserName }) => {
+    test.skip(
+      browserName !== 'chromium',
+      'desktop WebKit has no TouchEvent constructor to build the gesture from',
+    );
+
+    await app.setViewportSize(PHONE);
+    await app.getByTestId('tab-tracks').click();
+    await expect(app.getByTestId('main-content')).toHaveAttribute(
+      'data-active-view',
+      'tracks',
+    );
+  });
+
+  test.afterEach(async ({ app }) => {
+    await app.setViewportSize({ width: 1440, height: 900 });
+  });
+
+  /**
+   * Drag the first row sideways by a fraction of its own width and
+   * lift. `fraction` is against the row, because the commit threshold
+   * is — a number of pixels here would be a second declaration of it,
+   * right on one viewport and wrong on the next.
+   */
+  const swipeFirstRow = (page: Page, fraction: number) =>
+    page.evaluate((f) => {
+      const row = document
+        .querySelector('track-list')
+        ?.shadowRoot?.querySelector('.track-row');
+
+      if (!row) throw new Error('no track row to swipe');
+
+      const box = row.getBoundingClientRect();
+      const y = box.top + box.height / 2;
+      const at = (x: number) =>
+        new Touch({
+          identifier: 1,
+          target: row,
+          clientX: box.left + x,
+          clientY: y,
+        });
+      const send = (type: string, points: Touch[]) =>
+        row.dispatchEvent(
+          new TouchEvent(type, {
+            bubbles: true,
+            composed: true,
+            cancelable: true,
+            touches: points,
+            changedTouches: points.length > 0 ? points : [at(0)],
+          }),
+        );
+
+      send('touchstart', [at(0)]);
+
+      for (const step of [0.25, 0.5, 0.75, 1]) {
+        send('touchmove', [at(box.width * f * step)]);
+      }
+
+      send('touchend', []);
+    }, fraction);
+
+  /** How many tracks the backend says are in the queue. */
+  const queueLength = async (page: Page) => {
+    const state = await callBinding<{ tracks: unknown[] }>(
+      page,
+      'queue.Queue.GetState',
+    );
+
+    return state.tracks?.length ?? 0;
+  };
+
+  test('adds exactly one track to the real queue', async ({ app }) => {
+    const before = await queueLength(app);
+
+    await swipeFirstRow(app, 0.6);
+
+    await expect.poll(() => queueLength(app)).toBe(before + 1);
+
+    // Queued, not played: a swipe is not a tap, and the difference is
+    // what is on screen afterwards.
+    expect(
+      await app.getByTestId('main-content').getAttribute('data-active-view'),
+    ).toBe('tracks');
+  });
+
+  test('does nothing when the finger did not get far enough', async ({
+    app,
+  }) => {
+    const before = await queueLength(app);
+
+    await swipeFirstRow(app, 0.1);
+    await app.waitForTimeout(400);
+
+    expect(await queueLength(app)).toBe(before);
+  });
+});

e2e/support/fixtures.ts

@@ -140,6 +140,50 @@ export async function navigateTo(page: Page, view: string): Promise<void> {
     .waitFor({ state: 'attached' });
 }
 
+/**
+ * Open the queue the way a user at this viewport would.
+ *
+ * **The route differs by width and that is the feature, not an
+ * inconvenience.** Above 600px the bottom bar carries a queue button.
+ * Below it that button is gone (#59) and the queue is reached from the
+ * full-screen Now Playing view, which the mini player's art opens —
+ * "reachable only from Now Playing", which is what the issue asks for.
+ *
+ * It is here rather than in one spec because four files need it, and
+ * because a spec that hard-codes `#queue-button` is quietly asserting
+ * *which* route exists as well as what the queue does. Four of them
+ * were, which is how hiding one button failed ten tests about
+ * something else.
+ *
+ * The width is read from the page rather than passed, so a caller that
+ * resizes and then opens does not have to say so twice.
+ */
+export async function openTheQueue(page: Page): Promise<void> {
+  const toggle = page.locator('#queue-button');
+
+  if (await toggle.isVisible()) {
+    if ((await toggle.getAttribute('aria-expanded')) !== 'true') {
+      await toggle.click();
+    }
+
+    await expect(toggle).toHaveAttribute('aria-expanded', 'true');
+
+    return;
+  }
+
+  // The phone: through Now Playing. `open-now-playing` is the mini
+  // player's art, which is a button only below 600px.
+  if (
+    (await page.getByTestId('main-content').getAttribute('data-active-view')) !==
+    'now-playing'
+  ) {
+    await page.getByTestId('open-now-playing').click();
+  }
+
+  await page.getByTestId('npv-queue').click();
+  await expect(page.locator('#queue-panel')).toHaveAttribute('open', '');
+}
+
 /** Thin client for the dev-only /__test/ surface (backend/testctl). */
 export class TestCtl {
   constructor(private readonly baseURL: string) {}

frontend/bindings/yellowjacket/backend/player/player.ts

@@ -142,6 +142,18 @@ export function SetVolume(desiredVolume: $models.UserVolume): $CancellablePromis
     return $Call.ByID(1375836663, desiredVolume);
 }
 
+/**
+ * SystemOwnsVolume reports whether the platform's own control is the
+ * only volume control there is, so this app neither offers one nor
+ * remembers a level.
+ * 
+ * It is bound: the frontend renders no `<volume-control>` when it is
+ * true, at any width.
+ */
+export function SystemOwnsVolume(): $CancellablePromise<boolean> {
+    return $Call.ByID(1027623185);
+}
+
 /**
  * TrackLengthInSeconds returns the duration of the current track.
  */

frontend/index.css

@@ -7,6 +7,26 @@
 
 html {
     height: 100%;
+
+    /* #54.  The web view's own tap highlight -- the grey box a phone
+       draws over the bounding rect of whatever was tapped -- gone in
+       one declaration, because `-webkit-tap-highlight-color` is an
+       *inherited* property and an inherited property crosses a shadow
+       boundary.  So this reaches every one of the app's shadow roots
+       without a rule in any of them; before it, exactly one component
+       (`library-status-indicator`) set it and the box appeared
+       everywhere else.
+
+       What it costs is the only touch feedback several surfaces had,
+       which is why the rows, the tab bar and the shared menu items
+       grew a `:active` state in the same change: removing the wrong
+       feedback and leaving none is not an improvement.  The cards
+       already had one (`transform: scale(0.97)`).
+
+       `user-select` is the same argument one rule up and was already
+       done: the `*` rule at the top of this file is inherited into the
+       shadow roots too. */
+    -webkit-tap-highlight-color: transparent;
 }
 
 body {
@@ -426,6 +446,7 @@ body div.sidebar {
             "jobs-band" auto
             "main-panel" 1fr
             "bottom-bar" auto
+            "progress-line" auto
             "bottom-nav" auto
             / 1fr;
         /* Nothing may scroll sideways here.  On a desktop the shell is
@@ -501,7 +522,8 @@ body div.sidebar {
        expression of the same fact is a second thing to keep in step.
        The view carries its own queue button, because this is where
        that one lived. */
-    body:has(#main-content[data-active-view="now-playing"]) .bottom-bar {
+    body:has(#main-content[data-active-view="now-playing"]) .bottom-bar,
+    body:has(#main-content[data-active-view="now-playing"]) player-progress-line {
         display: none;
     }
 }
@@ -522,26 +544,58 @@ body div.sidebar {
     }
 
     /* Volume stands down here whatever the setting says, because this
-       is about room and about the platform rather than about
+       is about room: five controls and a slider do not fit a 360px
-       preference: the hardware keys own volume on a phone, which is
+       bar, and the full-screen now-playing view is where seeking and
-       also why mediacontrols' Android handler implements no volume
+       volume go on a phone. It moved from `audio-player`'s own media
-       callback. It moved from `audio-player`'s own media query when
+       query when #42 moved the control into the bar — same rule, and
-       #42 moved the control into the bar — same rule, and now stated
+       now stated where the element actually is.
-       where the element actually is.
 
-       `.bottom-bar volume-control`, not the one in
+       **This rule used to carry the platform argument too, and no
-       `now-playing-view`: that view is the phone's transport and is
+       longer does** (#64). "The hardware keys own the volume" is not a
-       where a slider does belong. */
+       width: it is false of a narrow desktop window and true of an
+       Android tablet, which this selector gets backwards both ways.
+       The player answers it now — `SystemOwnsVolume` — and
+       `volume-control` renders nothing when it is true, at every
+       width and in both of its mount points. What is left here is the
+       question a stylesheet can actually answer. */
     .bottom-bar volume-control {
         display: none;
     }
+
+    /* The queue leaves the phone's bar (#59), because #55 made it a
+       screen with an entry in the back stack and Now Playing already
+       carries its own button for it. The route is the mini player's
+       art -> Now Playing -> the queue, which is the "reachable only
+       from Now Playing" this issue asks for.
+
+       This is allowed to remove a control only because the control is
+       still reachable: plan 018's matrix promises that no action is
+       ever unreachable at any supported size, and that promise is what
+       `phone-transport.spec.ts` asserts rather than the button count.
+
+       **`.bottom-bar #queue-button`, not `#queue-button`**, and that is
+       not decoration. The rule this overrides is written *nested*
+       inside `.bottom-bar`, so it builds to a descendant selector one
+       class more specific than it looks in the source -- and a bare
+       `#queue-button` here loses to it, media query or not. Being last
+       in the file is not enough when the thing above is more specific,
+       which is the same lesson as this section's own header one level
+       down: nesting adds specificity the source does not show, and the
+       failure is silent (the button simply stayed). */
+    .bottom-bar #queue-button {
+        display: none;
+    }
 }
 
 /* Out of the desktop grid entirely.  `job-band` renders nothing above
    600px anyway, but an in-flow grid child with no named area is
    auto-placed into a row of the shell -- the same trap the skip link is
-   absolutely positioned to avoid. */
+   absolutely positioned to avoid.  `player-progress-line` (#58) is the
-body job-band {
+   same element in the same position for the same reason: below 600px it
+   has a named row, and above it there is no border for it to sit on --
+   the desktop bar carries a real, interactive seek bar. */
+body job-band,
+body player-progress-line {
     display: none;
 }
 
@@ -574,3 +628,21 @@ body job-band {
         background-color: var(--yj-bg-elevated, #343a40);
     }
 }
+
+/* #58.  How far through the song we are, in its own grid row between
+   the two bars -- so the line is *on* the border rather than inside
+   either of them, and in flow rather than over it.  The row is `auto`
+   and the element renders nothing while no track is loaded, so it costs
+   no height at all until there is something to say.
+
+   **This block is below the `display: none` above and has to be**, for
+   the reason the band's rule is: a media query adds no specificity, so
+   `body player-progress-line { display: block }` written before that
+   rule loses to it at equal specificity and the line never appears at
+   any width.  Nothing fails; it is simply not there. */
+@media (max-width: 599px) {
+    body player-progress-line {
+        display: block;
+        grid-area: progress-line;
+    }
+}

frontend/index.html

@@ -81,6 +81,16 @@
             </button>
         </div>
     </footer>
+    <!-- How far through the song we are, on the border between the two
+         bars (#58). The shell's element rather than either bar's:
+         they are separate components stacked in this grid, so a line
+         on the border between them is a row of it, and neither one has
+         to reach into the other's box for two pixels. It renders
+         nothing above 600px and nothing with no track, is `aria-hidden`
+         (Now Playing's seek bar is what announces the position) and
+         takes no pointer events at all -- a thin line that sometimes
+         seeks is worse than one that never does. -->
+    <player-progress-line></player-progress-line>
     <!-- The phone's primary navigation, hidden above 600px by
          index.css.  Eager rather than a chunk, for the reason
          notification-host is: it is the only way to move around the

frontend/index.ts

@@ -21,6 +21,10 @@ import '@components/audio-player/audio-player.ts';
 // In the bar rather than inside `audio-player` since #42, so the shell
 // is what has to register it.
 import '@components/audio-player/volume-control/volume-control.ts';
+// The phone's progress line (#58), on the border between the mini
+// player and the tab bar. In the shell for the same reason the volume
+// is, and eager because it is part of the bottom bar's first paint.
+import '@components/audio-player/progress-line/progress-line.ts';
 import '@components/track-list/track-list.ts';
 import '@components/now-playing/now-playing.ts';
 import '@components/sidebar/app-sidebar.ts';
@@ -66,7 +70,7 @@ import '@store/theme-store';
 // registers the document keydown listener for global shortcuts.
 import './src/services/keyboard-shortcut-service';
 import { activateView, deactivateView } from '@utils/view-lifecycle';
-import { installLongPressContextMenu } from '@utils/long-press';
+import { installTouchGestures } from '@utils/touch-gestures';
 import { openQueue, queuePanelElement } from '@utils/open-queue';
 import { installTopBarFit } from './src/services/top-bar-fit';
 import {
@@ -83,10 +87,13 @@ setBasePath('/dist/webawesome');
 // the session.
 registerBundledIcons();
 
-// The touch equivalent of a right-click, installed once for every menu
+// Every touch gesture in the app, installed once rather than per
-// in the app rather than per component. Harmless on a desktop: it acts
+// component (plan 019). Harmless on a desktop: it acts on
-// on `pointerType === 'touch'` only.
+// `pointerType === 'touch'` only, per event, so a mouse on a
-installLongPressContextMenu();
+// touchscreen keeps click-selects / double-click-plays on the very
+// same row. An unclaimed long press still becomes a `contextmenu`,
+// which is what leaves all fourteen menus untouched by #63.
+installTouchGestures();
 
 // The top bar decides what it can afford to show (#143). Here rather
 // than in a component because the bar is light DOM in index.html and

frontend/scripts/check-css-literals.mjs

@@ -23,97 +23,23 @@
  * as the literal contains an unterminated `/*`. Nothing else produces
  * that, and a legitimate literal cannot contain one.
  */
-import { readFileSync } from 'node:fs';
+import { globSync, readFileSync } from 'node:fs';
-import { globSync } from 'node:fs';
+
+import { taggedLiterals } from './css-literals.mjs';
 
 const TAGS = ['css', 'html', 'svg'];
 
-/**
- * Find the end of a template literal that starts at `start` (the index
- * of its opening backtick), respecting escapes and `${}` substitutions.
- * Returns the index of the closing backtick, or -1.
- */
-function endOfTemplate(src, start) {
-  let depth = 0;
-
-  for (let i = start + 1; i < src.length; i++) {
-    const c = src[i];
-
-    if (c === '\\') {
-      i++;
-      continue;
-    }
-
-    if (c === '$' && src[i + 1] === '{') {
-      depth++;
-      i++;
-      continue;
-    }
-
-    if (c === '}' && depth > 0) {
-      depth--;
-      continue;
-    }
-
-    if (c === '`' && depth === 0) return i;
-  }
-
-  return -1;
-}
-
-/** Strip `${...}` substitutions, which may legitimately contain anything. */
-function stripSubstitutions(text) {
-  let out = '';
-  let depth = 0;
-
-  for (let i = 0; i < text.length; i++) {
-    if (text[i] === '$' && text[i + 1] === '{') {
-      depth++;
-      i++;
-      continue;
-    }
-
-    if (text[i] === '}' && depth > 0) {
-      depth--;
-      continue;
-    }
-
-    if (depth === 0) out += text[i];
-  }
-
-  return out;
-}
-
-function lineOf(src, index) {
-  return src.slice(0, index).split('\n').length;
-}
-
 const files = globSync('src/**/*.ts', { cwd: process.cwd() });
 const problems = [];
 
 for (const file of files) {
   const src = readFileSync(file, 'utf8');
-  const tagPattern = new RegExp(`(^|[^\\w$.])(${TAGS.join('|')})\``, 'g');
 
-  let match;
+  for (const { tag, body, line } of taggedLiterals(src, TAGS)) {
-
-  while ((match = tagPattern.exec(src)) !== null) {
-    const open = match.index + match[0].length - 1;
-    const close = endOfTemplate(src, open);
-
-    if (close === -1) continue;
-
-    const body = stripSubstitutions(src.slice(open + 1, close));
     const opens = (body.match(/\/\*/g) ?? []).length;
     const closes = (body.match(/\*\//g) ?? []).length;
 
-    if (opens > closes) {
+    if (opens > closes) problems.push({ file, line, tag });
-      problems.push({
-        file,
-        line: lineOf(src, open),
-        tag: match[2],
-      });
-    }
   }
 }
 

frontend/scripts/check-css-nesting.mjs

@@ -0,0 +1,79 @@
+#!/usr/bin/env node
+/**
+ * Fail on a nested rule whose selector starts with an element name.
+ *
+ * See `css-nesting.mjs` for what the phone does with one. No tier here
+ * can see it: the component tier, the e2e tier and `make ui-visual` all
+ * run a current Chromium, where the rule applies normally, so the only
+ * report is a screenshot of the device — which is how the bottom bar's
+ * title came to have never truncated there.
+ *
+ * It covers `index.css` and the `css` literals in the components alike,
+ * because a shadow-root stylesheet is parsed by the same engine.
+ */
+import { globSync, readFileSync } from 'node:fs';
+
+import { taggedLiterals } from './css-literals.mjs';
+import { findBareNestedRules } from './css-nesting.mjs';
+
+const problems = [];
+
+// Every stylesheet, not `index.css` by name: the hook that runs this
+// fires on `frontend/**/*.{ts,css}`, so naming one file promises a
+// coverage the sweep does not deliver -- a second stylesheet would be
+// silently unswept while the hook still went green over it. There is
+// only `index.css` today, which is exactly when this is free to fix.
+const stylesheets = globSync('*.css', { cwd: process.cwd() });
+
+if (stylesheets.length === 0) {
+  console.error('css-nesting-check: no stylesheet matched *.css');
+  process.exit(1);
+}
+
+for (const file of stylesheets) {
+  for (const { line, selector } of findBareNestedRules(
+    readFileSync(file, 'utf8'),
+  )) {
+    problems.push({ file, line, selector });
+  }
+}
+
+const sources = globSync('src/**/*.ts', { cwd: process.cwd() });
+
+// A sweep over an empty glob passes, and this one is expected to find
+// nothing, so "it found nothing" has to mean it looked.
+if (sources.length === 0) {
+  console.error('css-nesting-check: no sources matched src/**/*.ts');
+  process.exit(1);
+}
+
+for (const file of sources) {
+  const src = readFileSync(file, 'utf8');
+
+  for (const literal of taggedLiterals(src, ['css'])) {
+    for (const { line, selector } of findBareNestedRules(literal.body)) {
+      problems.push({ file, line: literal.line + line - 1, selector });
+    }
+  }
+}
+
+if (problems.length > 0) {
+  for (const p of problems) {
+    console.error(
+      `${p.file}:${p.line}: nested rule "${p.selector.split('\n')[0]}" starts ` +
+        'with an element name — write it as "& ' +
+        `${p.selector.split('\n')[0]}"`,
+    );
+  }
+
+  console.error(
+    `\ncss-nesting-check: ${problems.length} problem(s). ` +
+      'Chrome 113 (the device) drops a nested rule that does not start ' +
+      'with a symbol; the leading & is valid in both syntaxes.',
+  );
+  process.exit(1);
+}
+
+console.log(
+  `css-nesting-check: ${stylesheets.length} stylesheet(s) + ${sources.length} files, no bare nested rules`,
+);

frontend/scripts/css-literals.mjs

@@ -0,0 +1,103 @@
+/**
+ * Finding the `css` tagged templates in a TypeScript source.
+ *
+ * Two checks read them — the unterminated-comment one and the nesting
+ * one — and a second scanner would be a second thing to keep in step
+ * with how a template literal actually ends.
+ */
+
+/**
+ * Find the end of a template literal that starts at `start` (the index
+ * of its opening backtick), respecting escapes and `${}` substitutions.
+ * Returns the index of the closing backtick, or -1.
+ */
+export function endOfTemplate(src, start) {
+  let depth = 0;
+
+  for (let i = start + 1; i < src.length; i++) {
+    const c = src[i];
+
+    if (c === '\\') {
+      i++;
+      continue;
+    }
+
+    if (c === '$' && src[i + 1] === '{') {
+      depth++;
+      i++;
+      continue;
+    }
+
+    if (c === '}' && depth > 0) {
+      depth--;
+      continue;
+    }
+
+    if (c === '`' && depth === 0) return i;
+  }
+
+  return -1;
+}
+
+/**
+ * Strip `${...}` substitutions, which may legitimately contain anything.
+ *
+ * Newlines inside them are kept, so a line number taken from the
+ * stripped text still names the right line of the file it came from.
+ */
+export function stripSubstitutions(text) {
+  let out = '';
+  let depth = 0;
+
+  for (let i = 0; i < text.length; i++) {
+    if (text[i] === '$' && text[i + 1] === '{') {
+      depth++;
+      i++;
+      continue;
+    }
+
+    if (text[i] === '}' && depth > 0) {
+      depth--;
+      continue;
+    }
+
+    if (depth === 0) out += text[i];
+    else if (text[i] === '\n') out += '\n';
+  }
+
+  return out;
+}
+
+/** The 1-based line number of `index` in `src`. */
+export function lineOf(src, index) {
+  return src.slice(0, index).split('\n').length;
+}
+
+/**
+ * Every tagged template literal in `src` whose tag is in `tags`.
+ *
+ * `body` has its substitutions stripped and `line` is the line its
+ * opening backtick sits on, so `line + (n - 1)` is the file line of the
+ * body's own line `n`.
+ */
+export function taggedLiterals(src, tags) {
+  const pattern = new RegExp(`(^|[^\\w$.])(${tags.join('|')})\``, 'g');
+  const found = [];
+
+  let match;
+
+  while ((match = pattern.exec(src)) !== null) {
+    const open = match.index + match[0].length - 1;
+    const close = endOfTemplate(src, open);
+
+    if (close === -1) continue;
+
+    found.push({
+      tag: match[2],
+      body: stripSubstitutions(src.slice(open + 1, close)),
+      line: lineOf(src, open),
+    });
+  }
+
+  return found;
+}

frontend/scripts/css-nesting.mjs

@@ -0,0 +1,119 @@
+/**
+ * A nested rule whose selector starts with an element name is silently
+ * dropped on the phone.
+ *
+ * The device renders in Chrome 113, which predates relaxed CSS nesting
+ * (Chrome 120): before that a nested selector had to start with
+ * something that could not be read as the beginning of a declaration,
+ * so `.bottom-bar { audio-player { … } }` is not a parse error anyone
+ * would notice — the inner rule simply does not exist, on the phone and
+ * only on the phone. Three were live in `index.css`, one of them the
+ * `text-overflow: ellipsis` on the bottom bar's title, which had
+ * therefore never truncated on the device.
+ *
+ * `& audio-player` is valid in both syntaxes, so no nested rule here
+ * has any reason to omit it.
+ *
+ * Two things the detection has to get right:
+ *
+ * - **A rule directly inside an at-rule is not nested.**
+ *   `@media (…) { bottom-nav { … } }` at the top level is an ordinary
+ *   rule and is fine — and it is the majority of the matches a regex
+ *   over the file would produce. What decides it is whether a *style*
+ *   rule is somewhere above, not what the immediate parent is: inside
+ *   `.bar { @media (…) { audio-player { … } } }` the inner rule is
+ *   nested, at-rule in between or not.
+ * - **A declaration is not a rule.** `background: url(…)` and any
+ *   string or comment can hold a brace, so this tracks them rather than
+ *   matching lines.
+ */
+
+/** Does this selector start with an identifier, rather than a symbol? */
+function startsWithIdent(selector) {
+  return /^[A-Za-z_\u00A0-\uFFFF]/.test(selector);
+}
+
+/**
+ * Every nested style rule in `css` whose selector starts with an
+ * element name, as `{ line, selector }` with a 1-based line.
+ */
+export function findBareNestedRules(css) {
+  const found = [];
+  /** The blocks we are inside, innermost last: 'style' or 'at'. */
+  const stack = [];
+  /** The text since the last `{`, `}` or `;` — a prelude, if a `{` follows. */
+  let prelude = '';
+  let preludeLine = 1;
+  let line = 1;
+
+  const startPrelude = () => {
+    prelude = '';
+    preludeLine = line;
+  };
+
+  for (let i = 0; i < css.length; i++) {
+    const c = css[i];
+
+    if (c === '\n') {
+      line++;
+      if (prelude.trim() === '') preludeLine = line;
+      prelude += c;
+      continue;
+    }
+
+    if (c === '/' && css[i + 1] === '*') {
+      const end = css.indexOf('*/', i + 2);
+      const comment = css.slice(i, end === -1 ? css.length : end + 2);
+
+      line += (comment.match(/\n/g) ?? []).length;
+      i += comment.length - 1;
+      if (prelude.trim() === '') preludeLine = line;
+      continue;
+    }
+
+    if (c === '"' || c === "'") {
+      let j = i + 1;
+
+      while (j < css.length && css[j] !== c) {
+        if (css[j] === '\\') j++;
+        j++;
+      }
+
+      prelude += css.slice(i, j + 1);
+      i = j;
+      continue;
+    }
+
+    if (c === '{') {
+      const selector = prelude.trim();
+      const kind = selector.startsWith('@') ? 'at' : 'style';
+
+      if (
+        kind === 'style' &&
+        stack.includes('style') &&
+        startsWithIdent(selector)
+      ) {
+        found.push({ line: preludeLine, selector });
+      }
+
+      stack.push(kind);
+      startPrelude();
+      continue;
+    }
+
+    if (c === '}') {
+      stack.pop();
+      startPrelude();
+      continue;
+    }
+
+    if (c === ';') {
+      startPrelude();
+      continue;
+    }
+
+    prelude += c;
+  }
+
+  return found;
+}

frontend/src/components/artist-details/artist-details.ts

@@ -14,6 +14,7 @@ import {
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@components/cover-grid/cover-grid.js';
 import { designTokens } from '../../styles/tokens.css';
+import { backButton } from '../../styles/back-button.css';
 
 @customElement('artist-details')
 export class ArtistDetails extends LitElement {
@@ -40,7 +41,7 @@ export class ArtistDetails extends LitElement {
     /** Tracks the store's cached array reference to detect refreshes. */
     private lastAlbumsRef: library.Album[] | null = null;
 
-    static override styles = [designTokens, css`
+    static override styles = [designTokens, backButton, css`
         :host {
             display: flex;
             flex-direction: column;
@@ -66,31 +67,6 @@ export class ArtistDetails extends LitElement {
                 );
         }
 
-        .back-button {
-            display: flex;
-            align-items: center;
-            justify-content: center;
-            width: 32px;
-            height: 32px;
-            border: none;
-            border-radius: 50%;
-            background: var(
-                --yj-bg-overlay,
-                rgba(255, 255, 255, 0.06)
-            );
-            color: var(--yj-text-primary, #fff);
-            cursor: pointer;
-            flex-shrink: 0;
-            transition: background-color 0.15s ease;
-        }
-
-        .back-button:hover {
-            background: var(
-                --yj-bg-hover,
-                rgba(255, 255, 255, 0.12)
-            );
-        }
-
         .back-button wa-icon {
             font-size: 16px; /* back button — outside type scale */
         }

frontend/src/components/artists-view/artists-view.ts

@@ -26,14 +26,15 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import { ViewLifecycleMixin } from '@utils/view-lifecycle';
 import { RovingGridController } from '@utils/roving-grid';
 
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@components/playlist-picker/playlist-picker.js';
 import { dict, list } from '@utils/binding';
@@ -131,17 +132,17 @@ export class ArtistsView
     private contextMenuArtistId: number | null = null;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
     getPlaylistSubmenuPopup():
-        | WaPopup
+        | MenuTarget
         | undefined {
         return this.playlistSubmenuPopup;
     }
@@ -1336,11 +1337,8 @@ export class ArtistsView
 
     private renderContextMenu() {
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .contextMenuOpen}
             >
@@ -1434,13 +1432,12 @@ export class ArtistsView
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .playlistSubmenuOpen}
             >
@@ -1468,7 +1465,7 @@ export class ArtistsView
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 

frontend/src/components/audio-player/controls/player-controls.ts

@@ -1,22 +1,77 @@
-import { LitElement, html, css } from 'lit';
+import { LitElement, html, css, nothing } from 'lit';
-import { customElement, state } from 'lit/decorators.js';
+import { customElement, property, state } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import { PlayerController } from '@store/controllers/player-controller';
 import { queueStore } from '@store/queue-store';
 import type { RepeatMode } from '@store/queue-store';
 import { designTokens } from '../../../styles/tokens.css';
+import { PHONE_QUERY } from '../../../utils/breakpoints';
+
+/**
+ * The transport, in the two places it appears.
+ *
+ * **The context is a property and cannot be a media query**, which is
+ * the whole reason this exists (#56). Everywhere else in this app a
+ * component states what it drops at phone width itself, because a media
+ * query inside a shadow root is answered by the viewport and that is
+ * the honest signal. Here the two hosts want *different* answers at the
+ * *same* viewport: on a phone the bottom bar wants three controls sized
+ * for a thumb, and `now-playing-view` wants five, larger still. So the
+ * host says which context and the viewport says which size band, and
+ * neither one alone can express it.
+ *
+ * Measured at the reference device's 424x439 before this: every button
+ * here was **33x21px**, in both places, which is what #56 reports as
+ * "the most important thing in the mobile app and they are tiny".
+ */
+export type ControlsContext = 'bar' | 'full';
 
 @customElement('player-controls')
 export class PlayerControls extends LitElement {
   private player = new PlayerController(this);
   private unsubscribeQueue?: () => void;
 
+  /**
+   * Where these controls are drawn. `bar` is the bottom bar in both
+   * bands; `full` is the full-screen transport.
+   *
+   * Reflected so a spec can read it and so the stylesheet keys off one
+   * fact rather than a class the host has to remember to set.
+   */
+  @property({ type: String, reflect: true })
+  context: ControlsContext = 'bar';
+
   @state() private shuffleMode = false;
   @state() private repeatMode: RepeatMode = 'off';
 
+  /**
+   * Phone width, from `matchMedia` rather than from a media query,
+   * because what it decides is whether shuffle and repeat *exist* here
+   * — and a stylesheet can only decide whether they are painted.
+   * `job-band` and `search-trigger` are the same pattern for the same
+   * reason.
+   */
+  @state() private phone = false;
+
+  private media?: MediaQueryList;
+
+  private onMedia = (e: MediaQueryListEvent) => {
+    this.phone = e.matches;
+  };
+
+  /** Whether this is the phone's bottom bar, which carries three
+   *  controls rather than five. */
+  private get slim(): boolean {
+    return this.context === 'bar' && this.phone;
+  }
+
   override connectedCallback(): void {
     super.connectedCallback();
 
+    this.media = window.matchMedia(PHONE_QUERY);
+    this.phone = this.media.matches;
+    this.media.addEventListener('change', this.onMedia);
+
     const s = queueStore.getState();
     this.shuffleMode = s.shuffleMode;
     this.repeatMode = s.repeatMode;
@@ -37,6 +92,7 @@ export class PlayerControls extends LitElement {
   override disconnectedCallback(): void {
     super.disconnectedCallback();
     this.unsubscribeQueue?.();
+    this.media?.removeEventListener('change', this.onMedia);
   }
 
   static override styles = [designTokens, css`
@@ -58,6 +114,99 @@ export class PlayerControls extends LitElement {
       justify-content: center;
     }
 
+    /* ---------------------------------------------------------------
+       Sizes (#56).
+
+       44px is the floor everything here is sized to, and play/pause
+       alone goes above it -- "large play/pause, adequate prev/next" is
+       the Direction, and it is the one control the report calls "front
+       and centre".
+
+       They are stated as custom properties rather than on each button
+       so a context sets two numbers instead of five rules, and so the
+       icon scales with its target: a 44px box around a 16px glyph is a
+       big hit area that still looks tiny, which is half of what the
+       report is about.
+
+       **The desktop bar sets none of them and must not change at all.**
+       #56 is an Android issue; the desktop's buttons are 33x21 before
+       this and are 33x21 after it.
+
+       That is why the box rules take a zero fallback and the *font-size*
+       rules are scoped to the two contexts instead of sharing them. A
+       button does not inherit its font from its parent -- the UA
+       stylesheet gives it one -- so a generic font-size: inherit is
+       not the no-op it reads as: it moved the desktop's buttons from
+       33x21 to 36x24, silently, by taking them from the UA's 13.3px to
+       the shell's 16px. Measured before and after by stashing this
+       file, which is the only way that particular 3px shows up.
+       --------------------------------------------------------------- */
+    button {
+      min-width: var(--yj-control-target, 0);
+      min-height: var(--yj-control-target, 0);
+    }
+
+    button.play {
+      min-width: var(--yj-control-play-target, 0);
+      min-height: var(--yj-control-play-target, 0);
+    }
+
+    /* The phone's bottom bar: three controls, sized for a thumb.
+       Shuffle and repeat are not here -- see the render method, which
+       does not draw them rather than hiding them, because a control
+       that is display:none is still a thing the component claims to
+       have. They are on the full-screen view, which is one tap away
+       through the mini player's art (#59). */
+    @media (max-width: 599px) {
+      :host([context='bar']) {
+        --yj-control-target: 44px;
+        --yj-control-icon: 18px;
+        --yj-control-play-target: 56px;
+        --yj-control-play-icon: 24px;
+      }
+
+      :host([context='bar']) button {
+        font-size: var(--yj-control-icon);
+      }
+
+      :host([context='bar']) button.play {
+        font-size: var(--yj-control-play-icon);
+      }
+    }
+
+    /* The full-screen transport, at every width: this view *is* the
+       player, so the controls are the page rather than a strip of it. */
+    :host([context='full']) {
+      --yj-control-target: 44px;
+      --yj-control-icon: 20px;
+      --yj-control-play-target: 64px;
+      --yj-control-play-icon: 28px;
+    }
+
+    :host([context='full']) button {
+      font-size: var(--yj-control-icon);
+    }
+
+    :host([context='full']) button.play {
+      font-size: var(--yj-control-play-icon);
+    }
+
+    :host([context='full']) #player-control-buttons {
+      gap: 12px;
+    }
+
+    /* Secondary controls sit below the primary row rather than beside
+       it, which is the Direction's shape and is why this is a second
+       group in the DOM instead of a CSS order property: visual order
+       and focus order have to agree. */
+    .secondary {
+      display: flex;
+      justify-content: center;
+      align-items: center;
+      gap: 24px;
+      margin-top: 8px;
+    }
+
     button:hover {
       color: var(--yj-accent-text, #ffd43b);
     }
@@ -104,46 +253,107 @@ export class PlayerControls extends LitElement {
     queueStore.cycleRepeat();
   };
 
-  override render() {
+  /** Shuffle. Secondary: it changes how the queue behaves rather than
-    const playOrPauseIcon = this.player.isPlaying ? 'pause' : 'play';
+   *  what is playing now. */
-    const playOrPauseHandler = this.player.isPlaying
+  private renderShuffle() {
-      ? this.handlePauseClick
+    return html`
-      : this.handlePlayClick;
+      <button
+        class=${this.shuffleMode ? 'active' : ''}
+        aria-label="Shuffle"
+        aria-pressed=${this.shuffleMode}
+        @click=${this.handleShuffleClick}
+      >
+        <wa-icon name="shuffle"></wa-icon>
+      </button>
+    `;
+  }
 
-    const shuffleClass = this.shuffleMode ? 'active' : '';
+  /** Repeat, whose label spells the mode out because one icon covers
+   *  three states. */
+  private renderRepeat() {
     const repeatMode = this.repeatMode;
     const repeatClasses = [
       repeatMode !== 'off' ? 'active' : '',
       repeatMode === 'one' ? 'repeat-one' : '',
     ].filter(Boolean).join(' ');
 
+    return html`
+      <button
+        class=${repeatClasses}
+        aria-label=${`Repeat: ${repeatMode}`}
+        aria-pressed=${repeatMode !== 'off'}
+        @click=${this.handleRepeatClick}
+      >
+        <wa-icon name="repeat"></wa-icon>
+      </button>
+    `;
+  }
+
+  /** Previous, play/pause, next — the three that are always drawn, in
+   *  every context and at every width. Only play/pause takes the large
+   *  size: the Direction asks for "large play/pause, adequate
+   *  prev/next", and a row of identical squares says every action here
+   *  is equally likely, which is not true of play. */
+  private renderPrimary() {
+    const playOrPauseIcon = this.player.isPlaying ? 'pause' : 'play';
+    const playOrPauseHandler = this.player.isPlaying
+      ? this.handlePauseClick
+      : this.handlePlayClick;
+
+    return html`
+      <button
+        aria-label="Previous track"
+        @click=${this.handlePreviousClick}
+      >
+        <wa-icon name="backward-step"></wa-icon>
+      </button>
+      <button
+        class="play"
+        aria-label=${this.player.isPlaying ? 'Pause' : 'Play'}
+        @click="${playOrPauseHandler}"
+      >
+        <wa-icon name=${playOrPauseIcon}></wa-icon>
+      </button>
+      <button
+        aria-label="Next track"
+        @click=${this.handleNextClick}
+      >
+        <wa-icon name="forward-step"></wa-icon>
+      </button>
+    `;
+  }
+
+  /**
+   * Two arrangements, not two components.
+   *
+   * `bar` keeps the order it has always had — shuffle, prev, play,
+   * next, repeat, one row — so nothing about the desktop bar moves.
+   * `full` puts the primary three on their own row with the secondary
+   * pair beneath, which the Direction asks for.
+   *
+   * **The phone's bar draws three buttons rather than hiding two.** A
+   * `display: none` control is still in the component's shadow root,
+   * still in the accessibility tree's markup, and still something a
+   * `shadowAll('button')[4]` finds — so "the phone has three controls"
+   * would be true of the pixels and false of the element. They are
+   * reachable on the full-screen view, which the mini player's art
+   * opens, and through the global shortcuts.
+   */
+  override render() {
+    if (this.context === 'full') {
+      return html`
+        <div id="player-control-buttons">${this.renderPrimary()}</div>
+        <div class="secondary">
+          ${this.renderShuffle()}${this.renderRepeat()}
+        </div>
+      `;
+    }
+
     return html`
       <div id="player-control-buttons">
-        <button
+        ${this.slim ? nothing : this.renderShuffle()}
-          class=${shuffleClass}
+        ${this.renderPrimary()}
-          aria-label="Shuffle"
+        ${this.slim ? nothing : this.renderRepeat()}
-          aria-pressed=${this.shuffleMode}
-          @click=${this.handleShuffleClick}
-        >
-          <wa-icon name="shuffle"></wa-icon>
-        </button>
-        <button aria-label="Previous track" @click=${this.handlePreviousClick}>
-          <wa-icon name="backward-step"></wa-icon>
-        </button>
-        <button aria-label=${this.player.isPlaying ? 'Pause' : 'Play'} @click="${playOrPauseHandler}">
-          <wa-icon name=${playOrPauseIcon}></wa-icon>
-        </button>
-        <button aria-label="Next track" @click=${this.handleNextClick}>
-          <wa-icon name="forward-step"></wa-icon>
-        </button>
-        <button
-          class=${repeatClasses}
-          aria-label=${`Repeat: ${repeatMode}`}
-          aria-pressed=${repeatMode !== 'off'}
-          @click=${this.handleRepeatClick}
-        >
-          <wa-icon name="repeat"></wa-icon>
-        </button>
       </div>
     `;
   }

frontend/src/components/audio-player/progress-line/progress-line.ts

@@ -0,0 +1,204 @@
+import { LitElement, html, css, nothing } from 'lit';
+import { customElement, state } from 'lit/decorators.js';
+
+import { PlayerController } from '@store/controllers/player-controller';
+import { designTokens } from '../../../styles/tokens.css';
+import { PHONE_QUERY } from '../../../utils/breakpoints';
+
+/**
+ * How far through the song we are, on the border between the mini
+ * player and the tab bar (#58).
+ *
+ * The phone's bottom bar carries three controls and no seek bar — plan
+ * 016 B2 took it out, because 4px of height is not a thumb target and the
+ * full-screen `now-playing-view` is where seeking belongs. What went
+ * with it is the one thing a mini player is expected to say without
+ * being opened: how far through the song it is. This is that, and
+ * only that.
+ *
+ * Four things about it are load-bearing.
+ *
+ * **It is the shell's element, not either bar's.** The mini player and
+ * `<bottom-nav>` are separate components stacked in the shell's grid,
+ * so a line on the border between them is a row of the grid — either
+ * one drawing it means reaching into the other's box for two pixels.
+ *
+ * **It never counts.** The position is pushed at 1 Hz by the backend
+ * (`PlaybackPositionChanged`), and the interval here interpolates
+ * *between* those reports and is stopped and restarted by every one of
+ * them — the seek bar's rule, for the reason the seek bar has it: a
+ * local clock drifted 30 s away from the backend across four keyboard
+ * seeks. The `trackChangeId` and `seq` guards come along for the same
+ * reason: the store is a singleton, so a report about the previous
+ * track must not be adopted, and the same second reported twice still
+ * has to reset the interpolation.
+ *
+ * **It is not a control and cannot become one.** `aria-hidden` on the
+ * host and `pointer-events: none` throughout: the real progress is
+ * announced by the seek bar on Now Playing, and a 2px strip on the top
+ * edge of the tab bar that sometimes seeks is worse than one that
+ * never does. It is also where a thumb aiming at a tab lands.
+ *
+ * **It renders nothing above 600px**, from `matchMedia` rather than a
+ * media query, because that decides whether the element *exists* — and
+ * with it whether a 1 Hz interval runs for the life of every desktop
+ * session about a line nobody can see. `job-band`, `search-trigger`
+ * and `player-controls` are the same pattern for the same reason.
+ */
+
+/**
+ * The reporting cadence, matched. This is not the clock: it exists
+ * only so the line moves in the second between two reports, and its
+ * error is discarded by the next one rather than carried.
+ */
+const InterpolationIntervalMillis = 1000;
+
+@customElement('player-progress-line')
+export class PlayerProgressLine extends LitElement {
+    private player = new PlayerController(this);
+
+    /** Phone width. See the class comment: existence, not paint. */
+    @state() private phone = false;
+
+    /** Seconds into the track, from the last report plus interpolation. */
+    @state() private elapsed = 0;
+
+    private previousTrackChangeId = -1;
+
+    /** The sequence number of the last backend report applied. */
+    private previousPositionSeq = -1;
+
+    private timerID = -1;
+
+    private media?: MediaQueryList;
+
+    private onMedia = (e: MediaQueryListEvent) => {
+        this.phone = e.matches;
+    };
+
+    static override styles = [
+        designTokens,
+        css`
+            :host {
+                display: block;
+                /* Not a target, at any depth. */
+                pointer-events: none;
+            }
+
+            .track {
+                height: 2px;
+                background-color: var(--yj-bg-surface, #212529);
+            }
+
+            .fill {
+                height: 100%;
+                background-color: var(--yj-accent, #ffd43b);
+                /* scaleX off a full-width box rather than a width in
+                   percent, so the moving thing is a transform and the
+                   line costs no layout once a second. */
+                transform-origin: left center;
+            }
+        `,
+    ];
+
+    private get trackLength(): number {
+        return this.player.currentTrack?.trackLength ?? 0;
+    }
+
+    override connectedCallback(): void {
+        super.connectedCallback();
+
+        // Decorative in full: the seek bar on Now Playing is what
+        // announces the position, and this says the same thing without
+        // a name, a value or a way to act on it.
+        this.setAttribute('aria-hidden', 'true');
+
+        this.media = window.matchMedia(PHONE_QUERY);
+        this.phone = this.media.matches;
+        this.media.addEventListener('change', this.onMedia);
+    }
+
+    override disconnectedCallback(): void {
+        super.disconnectedCallback();
+        this.stopInterpolating();
+        this.media?.removeEventListener('change', this.onMedia);
+    }
+
+    override updated(): void {
+        // A track change resets the line, and `trackChangeId` is what
+        // reveals one when the same file plays twice in a row.
+        const currentChangeId = this.player.currentTrack?.trackChangeId ?? -1;
+
+        if (currentChangeId !== this.previousTrackChangeId) {
+            this.previousTrackChangeId = currentChangeId;
+            this.elapsed = this.player.currentTrack?.seekPosition ?? 0;
+            this.stopInterpolating();
+        }
+
+        // The backend's own position wins over anything counted here,
+        // and a report for a track that is no longer loaded is stale by
+        // definition.
+        const position = this.player.position;
+
+        if (
+            position &&
+            position.trackChangeId === currentChangeId &&
+            position.seq !== this.previousPositionSeq
+        ) {
+            this.previousPositionSeq = position.seq;
+            this.elapsed = position.positionSeconds;
+            this.stopInterpolating();
+        }
+
+        // One owner for the interval, as in `seek-bar`: everything that
+        // wants it started or stopped says so by changing state that
+        // brings us back here.
+        if (this.phone && this.player.isPlaying && currentChangeId !== -1) {
+            this.startInterpolating();
+        } else {
+            this.stopInterpolating();
+        }
+    }
+
+    private stopInterpolating(): void {
+        if (this.timerID !== -1) {
+            clearInterval(this.timerID);
+            this.timerID = -1;
+        }
+    }
+
+    private startInterpolating(): void {
+        if (this.timerID !== -1) {
+            return;
+        }
+
+        this.timerID = window.setInterval(() => {
+            if (this.elapsed < this.trackLength) {
+                this.elapsed += 1;
+            }
+        }, InterpolationIntervalMillis);
+    }
+
+    override render() {
+        // Nothing playing is nothing to say, and the grid row is `auto`
+        // so an empty render costs no height at all -- `job-band`'s
+        // rule one row down.
+        if (!this.phone || this.player.currentTrack === null) return nothing;
+
+        const length = this.trackLength;
+        const fraction =
+            length > 0 ? Math.min(1, Math.max(0, this.elapsed / length)) : 0;
+
+        return html`
+            <div class="track" data-testid="progress-line">
+                <div class="fill" style="transform: scaleX(${fraction})"></div>
+            </div>
+        `;
+    }
+}
+
+declare global {
+    interface HTMLElementTagNameMap {
+        'player-progress-line': PlayerProgressLine;
+    }
+}

frontend/src/components/audio-player/seekbar/seek-bar.ts

@@ -45,18 +45,6 @@ export class SeekBar extends LitElement {
   private showRemaining: boolean = true;
 
   static override styles = [designTokens, waSliderLabel, css`
-    /* 12px below the phone breakpoint. The bottom bar's seek bar is
-       display:none there (016 B2 phase 1), so the only instance a
-       viewport media query can reach at that width is the full-screen
-       now-playing view's -- which is exactly the one a thumb uses.
-       The track size lives on wa-slider inside this shadow root, so a
-       custom property set by the host would not reach it. */
-    @media (max-width: 599px) {
-      wa-slider {
-        --track-size: 12px;
-      }
-    }
-
     wa-slider {
       --track-size: 6px;
       flex: 1;
@@ -80,6 +68,57 @@ export class SeekBar extends LitElement {
       background: var(--yj-bg-base, black);
     }
 
+    /* The phone's seek bar, and this block is last on purpose.
+
+       A media query adds no specificity, so this lived above the plain
+       "wa-slider" rule and lost to it at every width: the 12px track it
+       asks for had never once applied, and the bar measured 261x6 on
+       the device while the source said 12. That is index.css's rule
+       ("the phone section is last on purpose") met inside a component's
+       own stylesheet, and nothing renders differently in any tier here
+       to say so.
+
+       The bottom bar's seek bar is display:none below this width (016
+       B2 phase 1), so the only instance a viewport media query can
+       reach is the full-screen now-playing view's -- which is exactly
+       the one a thumb uses. The desktop bar keeps its 6px, where a
+       mouse is precise and the thickness is right.
+
+       The painted track and the thing you can hit are allowed to
+       differ, and a slider is the clearest case where they should: 12px
+       is a progress bar you can see, and 44px is the app's touch floor
+       (#56). A 44px-*thick* bar would be wrong-looking and would cost
+       the album art the vertical space #51 spent an issue recovering.
+
+       Two things about how the target is built.
+
+       The padding goes on ::part(slider) rather than on the host,
+       because that inner div is what carries the gesture -- it has the
+       listener and the touch-action: none, and it is exactly the host's
+       size, so padding the host would grow a box that does not take the
+       press.
+
+       The padding is asymmetric and the margins cancel it, so the row
+       does not grow by the difference. Both halves are measured: the
+       seek row is 19px (its clocks, not the track, decide that) and the
+       play button's top edge is 8px below it, so the target takes the
+       space *above*, where .art is a non-interactive div. Growing the
+       row instead cost the art 25px of 143. Verified on the device at
+       424x439: hit area 44px, painted track 12px, row still 19px, art
+       still 143px, 8px of clearance left under the play button, a press
+       26px above the track seeks, and a hit test on the play button's
+       top edge still reaches the play button. */
+    @media (max-width: 599px) {
+      wa-slider {
+        --track-size: 12px;
+      }
+
+      wa-slider::part(slider) {
+        padding-block: 28px 4px;
+        margin-block: -28px -4px;
+      }
+    }
+
     #seek-bar-container {
       display: flex;
       justify-content: space-between;

frontend/src/components/audio-player/volume-control/volume-control.ts

@@ -1,4 +1,4 @@
-import { LitElement, html, css } from 'lit';
+import { LitElement, html, css, nothing } from 'lit';
 import { customElement, state } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/slider/slider.js';
@@ -27,6 +27,26 @@ export class VolumeControl extends LitElement {
   @state()
   private popup = volumeStyleStore.popup;
 
+  /**
+   * Whether there is a volume of ours to control at all (#64).
+   *
+   * The decision is made here rather than at either mount point,
+   * because there are two -- the bottom bar's copy lives in
+   * `index.html`, which has no module scope to make it conditional --
+   * and one of them is a control the shell cannot un-render. So the
+   * control answers for itself, and the bar and the phone's
+   * full-screen transport get the same answer without either knowing
+   * the question exists.
+   *
+   * It renders `nothing` *and* hides the host: an empty shadow root is
+   * what stops a positional or role query finding a button that cannot
+   * act, and `:host([hidden])` is what stops the element occupying a
+   * flex item's worth of the transport -- the `:host` display above
+   * outranks the UA's `[hidden]` rule, so it has to be said.
+   */
+  @state()
+  private available = volumeStyleStore.available;
+
   private unsubscribeStyle?: () => void;
 
   // Locally-tracked volume while the user is actively dragging or scrolling.
@@ -43,6 +63,13 @@ export class VolumeControl extends LitElement {
       align-items: center;
     }
 
+    /* See the available field. A gap is only drawn between boxes,
+       so a hidden host costs its parent nothing -- which is where the
+       29px this gives back to Now Playing comes from (#172). */
+    :host([hidden]) {
+      display: none;
+    }
+
     button {
       background: none;
       border: none;
@@ -154,12 +181,15 @@ export class VolumeControl extends LitElement {
 
     this.unsubscribeStyle = volumeStyleStore.subscribe(() => {
       this.popup = volumeStyleStore.popup;
+      this.setAvailable(volumeStyleStore.available);
 
       // Switching to the slider while the popup is open would leave the
       // document listener installed for a popup that no longer renders.
       if (!this.popup) this.closeSlider();
     });
 
+    this.setAvailable(volumeStyleStore.available);
+
     void volumeStyleStore.init();
   }
 
@@ -233,7 +263,25 @@ export class VolumeControl extends LitElement {
   // RENDER
   // ===================================================================
 
+  /**
+   * `hidden` is set imperatively rather than reflected from the state,
+   * because it has to be on the *host* and a `@state` does not reflect.
+   * It is the right attribute besides: it takes the element out of the
+   * accessibility tree as well as out of the layout.
+   */
+  private setAvailable(available: boolean) {
+    this.available = available;
+    this.hidden = !available;
+
+    // A popup left open when the control goes away would keep its
+    // document click listener installed for markup that no longer
+    // renders.
+    if (!available) this.closeSlider();
+  }
+
   override render() {
+    if (!this.available) return nothing;
+
     const muted = this.player.muted;
 
     // Inline, the icon is the mute toggle rather than a disclosure:

frontend/src/components/autotag-view/autotag-view.ts

@@ -250,13 +250,20 @@ export class AutotagView extends ViewLifecycleMixin(LitElement) {
             }
 
             /* Collapsible-section toggle used in the Pending header —
-               transparent button that inherits the header's type. */
+               transparent button that inherits the header's type.
+
+               187x**15** before this (#186), which was the smallest
+               control measured anywhere in the app until the column
+               arrows were counted. It is transparent and full-width
+               already, so the floor costs it a height and nothing
+               else. */
             .section-toggle {
                 display: flex;
                 align-items: center;
                 gap: 0.35rem;
                 flex: 1;
                 min-width: 0;
+                min-block-size: 44px;
                 padding: 0;
                 background: transparent;
                 border: 0;
@@ -274,6 +281,8 @@ export class AutotagView extends ViewLifecycleMixin(LitElement) {
                 color: var(--yj-text-tertiary, #888);
             }
 
+            /* 32x18, and it has no background until hover -- so the
+               padding out to a square target is invisible (#186). */
             .folders-menu-trigger {
                 background: transparent;
                 border: 0;
@@ -281,6 +290,8 @@ export class AutotagView extends ViewLifecycleMixin(LitElement) {
                 font-size: 1.1rem;
                 line-height: 1;
                 padding: 0.1rem 0.4rem;
+                min-inline-size: 44px;
+                min-block-size: 44px;
                 border-radius: 3px;
                 cursor: pointer;
             }
@@ -293,7 +304,10 @@ export class AutotagView extends ViewLifecycleMixin(LitElement) {
             .folders-refresh-trigger {
                 display: flex;
                 align-items: center;
+                justify-content: center;
                 font-size: 0.95rem;
+                min-inline-size: 44px;
+                min-block-size: 44px;
             }
 
             .folders-refresh-trigger:disabled {

frontend/src/components/bottom-nav/bottom-nav.ts

@@ -27,15 +27,43 @@ interface Tab {
  * three to five items before the targets stop being thumb-sized —
  * 360 px over eleven sidebar entries is 32 px each — so the four here
  * are the ones plan 016's subset says a phone is *for*, and "More"
- * opens the existing `<app-sidebar>` in a drawer. That is deliberately
+ * opens the existing `<app-sidebar>` in a sheet. That is deliberately
  * a reuse rather than a second nav: two lists of destinations is two
  * places to add the next view to, and the sidebar already carries the
  * drag-to-navigate behaviour, the active state and the labels.
  *
+ * **"More" rises from the bottom, and it is the same sheet a context
+ * menu is** (#71). It was a `wa-drawer` sliding in from the side: a
+ * 200px column of a 424px screen, opening away from the thumb that
+ * asked for it, with three nested scrollers in it — the dialog, its
+ * body, and the sidebar's own `overflow-y: auto` host — which is the
+ * "only part of the screen scrolls under my finger" in the report.
+ *
+ * Three things about the replacement are load-bearing.
+ *
+ * **It is the same element with another `placement`, not a new
+ * surface.** `wa-drawer` renders a native `<dialog>` and opens it with
+ * `showModal()`, which is exactly what `menu-surface`'s sheet relies
+ * on — Chrome 37, the real top layer — so #60's containment finding
+ * carries over with nothing new to prove, and the focus trap, Escape,
+ * tap-outside and `wa-after-hide` all come along unchanged.
+ *
+ * **The body is the only scroller**, with `overscroll-behavior:
+ * contain`, and the sidebar is told to stop being one. Nesting them is
+ * what makes a drag scroll the wrong box.
+ *
+ * **The sidebar is still mounted rather than re-listed as data**,
+ * which the issue offers as an alternative. Its `data-testid` per
+ * destination is the reason: the shell's own sidebar is `display:
+ * none` below 600px rather than removed, so a second list drawing
+ * `nav-*` handles is the duplication this component already renders
+ * conditionally to avoid — and it would be a second place to add the
+ * next view to, with its own copy of #25's visibility filter.
+ *
  * It emits the same bubbling, composed `navigate` event the sidebar
  * does, so `index.ts` needs no knowledge of it, and it listens for that
  * event globally for the same reason the sidebar does: a navigation it
- * did not send (a card click, a detail view, the drawer) still has to
+ * did not send (a card click, a detail view, the sheet) still has to
  * move the highlight.
  */
 @customElement('bottom-nav')
@@ -89,6 +117,17 @@ export class BottomNav extends LitElement {
             color: var(--yj-accent, #ffd43b);
         }
 
+        /* The press state (#54). This bar is the phone's primary
+           navigation and had no feedback of its own at all -- what a
+           tap produced was the web view's tap highlight, a grey box
+           over the whole 48px cell, which index.css has now taken
+           away. The .active rule above is which tab you are *on*; this
+           is the tab being pressed, so they are a colour and a
+           background rather than two colours. */
+        button:active {
+            background-color: var(--yj-press-overlay, rgba(255, 255, 255, 0.12));
+        }
+
         button:focus-visible {
             outline: 2px solid var(--yj-accent, #ffd43b);
             outline-offset: -2px;
@@ -104,15 +143,50 @@ export class BottomNav extends LitElement {
             white-space: nowrap;
         }
 
-        wa-drawer::part(body) {
+        /* The sheet. --size is the drawer's own API for the axis its
-            padding: 0;
+           placement uses, so auto is what makes it hug its content
+           instead of being a fixed 25rem band; the rest is the shape
+           the menu-surface context sheet already has, so a phone meets
+           one sheet rather than two. 85vh for its reason too: a surface
+           covering the whole screen is a page, not a sheet. */
+        wa-drawer {
+            --size: auto;
         }
 
-        app-sidebar {
+        wa-drawer::part(dialog) {
-            /* The sidebar sizes itself inline and collapses to icons
+            max-height: 85vh;
-               below 900px, which is every phone.  In the drawer there
+            border-radius: 12px 12px 0 0;
-               is room for the labels, so it is told not to. */
+            /* The sidebar paints its own surface, so the sheet takes
-            height: 100%;
+               that colour rather than the menus' elevated one: two
+               greys in one sheet is a seam across the middle of it. */
+            background-color: var(--yj-bg-surface, #212529);
+            /* One scroller, and it is the body below. The dialog's own
+               overflow: auto is what let the sheet scroll as well as
+               its content, and it is also what would square off the
+               corners this rule just rounded. */
+            overflow: hidden;
+        }
+
+        wa-drawer::part(body) {
+            padding: 0;
+            /* A scroll that reaches the end of this list must not
+               become a scroll of the page underneath it. */
+            overscroll-behavior: contain;
+            /* The sheet sits on the bottom edge, so the last
+               destination would otherwise be under the home indicator
+               on a gesture-navigation phone -- the same allowance the
+               bar itself makes above. */
+            padding-bottom: env(safe-area-inset-bottom, 0);
+        }
+
+        /* A sheet is dragged at with a thumb, so it says where its top
+           edge is. Decorative: the destinations are below it. */
+        .grip {
+            width: 36px;
+            height: 4px;
+            margin: 8px auto 4px;
+            border-radius: 2px;
+            background: var(--yj-text-tertiary, #888);
         }
     `];
 
@@ -147,7 +221,7 @@ export class BottomNav extends LitElement {
     private visibilityCtrl = new ViewVisibilityController(this);
 
     /**
-     * Whether the drawer has been asked for.
+     * Whether the sheet has been asked for.
      *
      * The sidebar inside it is rendered only while this is true, and
      * that is not an optimisation. `app-sidebar` carries a
@@ -189,15 +263,17 @@ export class BottomNav extends LitElement {
 
     override updated() {
         // Web Awesome renders its heading into its own shadow root and
-        // never points aria-labelledby at it, so the drawer would
+        // never points aria-labelledby at it, so the sheet would
         // otherwise be announced unnamed -- the same fix, and the same
         // reason, as every wa-dialog in the app. A drawer's shadow root
-        // has the same shape, so the helper needs no change.
+        // has the same shape, so the helper needs no change; under
+        // `without-header` there is no heading to point at, which is
+        // that helper's documented `aria-label` path.
         nameDialog(this.drawer);
     }
 
     private onGlobalNavigate = () => {
-        // A navigation from inside the drawer is the drawer's job done.
+        // A navigation from inside the sheet is the sheet's job done.
         // The highlight is not this listener's business any more.
         this.drawerOpen = false;
     };
@@ -263,12 +339,14 @@ export class BottomNav extends LitElement {
             </nav>
 
             <wa-drawer
-                placement="start"
+                placement="bottom"
+                without-header
                 label="All views"
                 data-testid="nav-drawer"
                 ?open=${this.drawerOpen}
                 @wa-after-hide=${this.onDrawerHide}
             >
+                <div class="grip"></div>
                 ${this.drawerOpen
                     ? html`<app-sidebar expanded></app-sidebar>`
                     : nothing}

frontend/src/components/config-page/config-field.ts

@@ -85,6 +85,21 @@ export class ConfigField extends LitElement {
             gap: 0.5em;
         }
 
+        /* Every control here meets the app's 44px touch floor (#186).
+
+           This is the shape every row in Settings uses, so it is the
+           one rule that covers the most controls -- and it is the
+           *cheapest* place to reach the floor, because there is no
+           overflow fit on this page. The page header's had one (#69),
+           which is why that pass had to grow padding and hand the
+           width back with a negative margin; here the control is a
+           block in a column and a taller box costs nothing but the
+           height it takes.
+
+           Measured on the reference device before this: the select
+           335x30, the text and number inputs the same, the browse
+           button 30 tall, the colour swatch 33x33 and the toggle
+           **34x19**. */
         input[type='text'],
         input[type='number'] {
             background: var(--yj-bg-elevated, #343a40);
@@ -95,6 +110,7 @@ export class ConfigField extends LitElement {
             font-size: 0.85em;
             font-family: inherit;
             min-width: 0;
+            min-block-size: 44px;
             flex: 1;
         }
 
@@ -117,6 +133,7 @@ export class ConfigField extends LitElement {
             font-size: 0.85em;
             font-family: inherit;
             cursor: pointer;
+            min-block-size: 44px;
             flex: 1;
         }
 
@@ -139,6 +156,7 @@ export class ConfigField extends LitElement {
             font-size: 0.85em;
             cursor: pointer;
             white-space: nowrap;
+            min-block-size: 44px;
         }
 
         button:hover {
@@ -158,8 +176,12 @@ export class ConfigField extends LitElement {
         }
 
         input[type='color'] {
-            width: 2.5em;
+            /* border-box, or the 2px border makes this 48 and the
-            height: 2.5em;
+               assertion below reads as passing by four pixels of
+               border rather than by the rule. */
+            box-sizing: border-box;
+            width: 44px;
+            height: 44px;
             border: 2px solid var(--yj-border, #444);
             border-radius: 4px;
             padding: 0;
@@ -187,12 +209,32 @@ export class ConfigField extends LitElement {
             display: flex;
             align-items: center;
             justify-content: space-between;
+            min-block-size: 44px;
         }
 
+        /* The toggle is the one control here whose target and paint
+           must differ, and it is also the one no sweep can see.
+
+           Its <input> is opacity: 0; width: 0; height: 0, so a
+           walk of every input on the page skips it as a zero-sized
+           node -- the thing a finger actually hits is this <label>,
+           which measured **34x19**. That is smaller than anything in
+           #186's original table and it is absent from it for exactly
+           that reason.
+
+           A 44px pill is not what a switch should look like, so the
+           box is 44px and the paint is not: .toggle-slider is a
+           2.5em x 1.4em child centred in it rather than an absolute
+           fill. The negative inline margins hand the extra width back
+           to the layout, so the pill stays flush with the right edge
+           of the inputs in the rows above it -- the header pass's
+           shape, used here for alignment rather than for a fit. */
         .toggle-switch {
-            position: relative;
+            display: grid;
-            width: 2.5em;
+            place-items: center;
-            height: 1.4em;
+            inline-size: 44px;
+            block-size: 44px;
+            margin-inline: calc((2.5em - 44px) / 2);
         }
 
         .toggle-switch input {
@@ -202,9 +244,10 @@ export class ConfigField extends LitElement {
         }
 
         .toggle-slider {
-            position: absolute;
+            position: relative;
             cursor: pointer;
-            inset: 0;
+            inline-size: 2.5em;
+            block-size: 1.4em;
             background: var(--yj-bg-overlay, #495057);
             border-radius: 1em;
             transition: background 0.2s;

frontend/src/components/config-page/config-page.ts

@@ -176,6 +176,13 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
             cursor: pointer;
             transition: background-color 0.15s ease;
             white-space: nowrap;
+            /* The app's 44px touch floor (#56, #186), stated once for
+               all 41 buttons this page renders rather than per class.
+               Height is free here: Settings has no overflow fit, so
+               the header's "only width is contested" rule does not
+               bind, and the two classes that need more than a height
+               say so below. */
+            min-block-size: 44px;
         }
 
         button:disabled {
@@ -509,11 +516,24 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
             margin: 0;
         }
 
+        /* The two column lists are the densest thing in the app, and
+           the density argument is why they are shaped the way they
+           are rather than simply grown (#186).
+
+           Measured on the reference device: the row was already
+           335x36 -- it is the controls *inside* it that were 16x16 and
+           **16x14**, the smallest anywhere in this app, 36 of them.
+           So the fix grows the controls into the row they already
+           occupy and only takes the row from 36 to 44, which over the
+           two lists (10 and 19 items) is 232px of extra scroll on a
+           439px screen. Growing each control to its own 44px row
+           instead would have cost four screens. */
         .column-item {
             display: flex;
-            align-items: center;
+            align-items: stretch;
             gap: 0.5em;
-            padding: 0.5em 0.75em;
+            padding: 0 0.75em;
+            min-block-size: 44px;
             border-bottom: 1px solid
                 var(--yj-border-subtle, #333);
             font-size: 0.85em;
@@ -531,8 +551,19 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
             color: var(--yj-text-tertiary, #888);
         }
 
+        /* A native checkbox cannot grow its hit area without growing
+           its paint, and a 44px checkbox is not what anyone wants. So
+           the target is the label instead: .column-label is a real
+           <label for> now, which makes the column's *name* the thing
+           you tap -- ~250x44 rather than 16x16.
+
+           That is the argument config-field already makes one file
+           over for its own labels: "a real label association also
+           makes the label text a click target for the control, which
+           is behaviour, not annotation". Here it is the whole fix. */
         .column-toggle {
             cursor: pointer;
+            align-self: center;
             accent-color: var(
                 --yj-accent,
                 #ffd43b
@@ -541,20 +572,32 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
 
         .column-label {
             flex: 1;
+            display: flex;
+            align-items: center;
+            cursor: pointer;
+            min-block-size: 44px;
         }
 
         .view-note {
             color: var(--yj-text-tertiary, #888);
             font-size: var(--yj-font-size-sm, 0.85rem);
             margin-left: auto;
+            /* The row stretches its children so the label can be a
+               full-height target; this is text, not a target. */
+            align-self: center;
         }
 
         .column-arrows {
             display: flex;
+            align-items: stretch;
             gap: 0.15em;
             margin-left: auto;
         }
 
+        /* 16x14 before this, and they carry background: none and a
+           transparent border -- so padding out to 44px grows the
+           target and changes nothing anyone can see until hover,
+           which is precisely what #186's Direction asks for. */
         .column-arrow-btn {
             background: none;
             border: 1px solid transparent;
@@ -564,6 +607,8 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
             font-size: 0.65em;
             line-height: 1;
             padding: 0.2em 0.35em;
+            min-inline-size: 44px;
+            min-block-size: 44px;
             transition:
                 color 0.15s,
                 border-color 0.15s;
@@ -711,6 +756,11 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
             padding: 0.2em 0.4em;
             letter-spacing: 2px;
             border-radius: 4px;
+            /* Square, so it needs the width too -- the shared rule
+               above only gives it a height. It was 31x31, and it is
+               the only route to "Remove library", which is the case
+               #55 settled one component over: the way out is 44px. */
+            min-inline-size: 44px;
         }
 
         .overflow-btn:hover {
@@ -2003,6 +2053,7 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
                                 class="column-item ${checked ? 'enabled' : 'disabled'}"
                             >
                                 <input
+                                    id="view-${v.id}"
                                     type="checkbox"
                                     class="column-toggle"
                                     aria-label="Show ${v.label} in the navigation"
@@ -2014,9 +2065,9 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
                         (e.target as HTMLInputElement).checked,
                     )}
                                 />
-                                <span class="column-label">
+                                <label class="column-label" for="view-${v.id}">
                                     ${v.label}
-                                </span>
+                                </label>
                                 ${note
                     ? html`<span class="view-note">${note}</span>`
                     : nothing}
@@ -2212,6 +2263,7 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
                                 class="column-item ${checked ? 'enabled' : 'disabled'}"
                             >
                                 <input
+                                    id="column-${id}"
                                     type="checkbox"
                                     class="column-toggle"
                                     aria-label="Show the ${columnLabel} column"
@@ -2222,11 +2274,12 @@ export class ConfigPage extends ViewLifecycleMixin(LitElement) {
                                             id,
                                         )}
                                 />
-                                <span
+                                <label
                                     class="column-label"
+                                    for="column-${id}"
                                 >
                                     ${columnLabel}
-                                </span>
+                                </label>
                                 <span
                                     class="column-arrows"
                                 >

frontend/src/components/config-page/download-clients.ts

@@ -8,6 +8,7 @@ import '@awesome.me/webawesome/dist/components/switch/switch.js';
 import '@awesome.me/webawesome/dist/components/spinner/spinner.js';
 import '@awesome.me/webawesome/dist/components/callout/callout.js';
 import { designTokens } from '../../styles/tokens.css';
+import { waTouchFloor } from '../../styles/wa-touch-floor.css';
 import type {
     DownloadDescriptor,
     DownloadProvider,
@@ -136,6 +137,7 @@ export class DownloadClients extends LitElement {
 
     static override styles = [
         designTokens,
+        waTouchFloor,
         css`
             :host {
                 display: block;
@@ -239,12 +241,17 @@ export class DownloadClients extends LitElement {
                 margin-top: 0.4em;
             }
 
+            /* The checkbox is 16x16 and cannot grow without becoming
+               a 44px checkbox, but it is already wrapped in the label
+               that names it -- so the label is the target and only
+               needs the height (#186). Eight of them. */
             .format-option {
                 display: flex;
                 align-items: center;
                 gap: 0.4em;
                 font-size: 0.9em;
                 cursor: pointer;
+                min-block-size: 44px;
             }
         `,
     ];

frontend/src/components/config-page/shortcut-capture.ts

@@ -25,6 +25,11 @@ export class ShortcutCapture extends LitElement {
         :host {
             display: inline-block;
         }
+        /* 80x25, twenty-six of them -- the most numerous control on
+           the Settings page after the column lists (#186). The floor
+           is a height here and nothing else: the width was already
+           past it, and the type stays where it is so a shortcut still
+           reads as a key rather than as a button. */
         button {
             font-family: inherit;
             font-size: var(--yj-text-sm, 13px);
@@ -35,6 +40,7 @@ export class ShortcutCapture extends LitElement {
             color: var(--yj-text-primary, #eee);
             cursor: pointer;
             min-width: 80px;
+            min-height: 44px;
             text-align: center;
             transition:
                 border-color 0.15s,
@@ -61,6 +67,11 @@ export class ShortcutCapture extends LitElement {
                 opacity: 0.7;
             }
         }
+        /* Reset renders only for a rebound shortcut, so a sweep of a
+           freshly-installed app never sees it -- it is not in #186's
+           tables for that reason, and it is a touch target the moment
+           anybody uses the feature. It also has no background, so the
+           padding out to 44px is invisible. */
         .reset-btn {
             font-size: var(--yj-text-xs, 11px);
             padding: 2px 6px;
@@ -69,7 +80,8 @@ export class ShortcutCapture extends LitElement {
             background: transparent;
             color: var(--yj-text-tertiary, #888);
             cursor: pointer;
-            min-width: auto;
+            min-width: 44px;
+            min-height: 44px;
             opacity: 0;
             transition: opacity 0.15s;
         }
@@ -79,6 +91,17 @@ export class ShortcutCapture extends LitElement {
         .reset-btn:hover {
             color: var(--yj-accent-text, #ffd43b);
         }
+        /*
+         * Reset is the only way to put a rebound shortcut back, so where
+         * the device has no hover it is always visible rather than an
+         * invisible button holding its hit area. The inverse of #68's
+         * rule, which applies where the hover control is redundant.
+         */
+        @media not all and (hover: hover) {
+            .reset-btn {
+                opacity: 1;
+            }
+        }
     `;
 
     private handleClick = () => {

frontend/src/components/cover-grid/cover-grid.ts

@@ -23,7 +23,8 @@ import { gridColumnsFor, gridSpacingFor } from '@utils/grid-spacing';
 import { queueStore } from '@store/queue-store';
 import type { QueueSource } from '@store/queue-store';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@components/playlist-picker/playlist-picker.js';
@@ -51,9 +52,11 @@ import {
     ContextMenuController,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import { creditLink, exploreLinkStyles } from '../../utils/explore-link';
+import { goToMenuItems } from '../../utils/go-to-menu';
+import type { GoToTarget } from '../../utils/go-to-menu';
 import { creditStore } from '@store/credit-store';
 import {
     createAlbumArtDragImage,
@@ -415,17 +418,17 @@ export class CoverGrid
     splitIndex = 0;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     // ContextMenuHost interface.
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -2083,15 +2086,36 @@ export class CoverGrid
         );
     }
 
+    /**
+     * The artist an album card's menu can navigate to — the card's own
+     * credit line, which stops being a link below the phone breakpoint
+     * (#67).
+     *
+     * A *track* target gets nothing: the dropdown's rows carry no
+     * links of their own, and the album they sit under is the card
+     * that opened them.
+     */
+    private get goToTarget(): GoToTarget | undefined {
+        if (this.contextMenuTarget.kind !== 'album') return undefined;
+
+        const album = this.albums.find(
+            (a) => a.ID === this.contextMenuAlbumId,
+        );
+
+        if (!album) return undefined;
+
+        return {
+            artistName: album.ArtistName,
+            artistMBID: album.ArtistMBID,
+        };
+    }
+
     private renderContextMenu() {
         const { ctxMenu } = this;
 
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${ctxMenu.contextMenuOpen}
             >
                 ${ctxMenu.contextMenuOpen
@@ -2201,16 +2225,20 @@ export class CoverGrid
                                         </wa-dropdown-item>
                                     `
                                   : nothing}
+                              ${goToMenuItems(this.goToTarget, {
+                                  onSelect: () => ctxMenu.close(),
+                                  onHover: () =>
+                                      ctxMenu.closePlaylistSubmenu(),
+                              })}
                           </div>
                       `
                 : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${ctxMenu.playlistSubmenuOpen}
             >
                 ${ctxMenu.playlistSubmenuOpen
@@ -2232,7 +2260,7 @@ export class CoverGrid
                           </div>
                       `
                 : nothing}
-            </wa-popup>
+            </menu-surface>
 
             <track-details></track-details>
         `;

frontend/src/components/downloads-view/downloads-view.ts

@@ -93,8 +93,26 @@ export class DownloadsView extends ViewLifecycleMixin(LitElement) {
                 border-bottom: 1px solid var(--yj-bg-overlay, rgba(255, 255, 255, 0.08));
             }
 
+            /* 85x34 and 96x34 before this (#186). A tab is the only
+               route to the panel it names, so it is the last control
+               that should be hard to hit -- and the underline that
+               marks the active one is drawn on the bottom border,
+               which a taller box moves further from the label. So the
+               height goes on *padding*, keeping the border against
+               the label rather than 10px below a centred one.
+
+               The min-size is the floor and is not redundant: padding
+               alone made this 44px here and **43px in CI**, because
+               the total is 13 + 13 + 2 + whatever line box the font
+               gives 13px text, and ubuntu:24.04's is a pixel shorter
+               than this machine's. A height computed from a font's
+               line box is not a height you control -- the same
+               mistake #195 made about a layout property measured on
+               one engine, one layer down, and caught here by the test
+               rather than by a person. */
             .tab {
-                padding: 8px 14px;
+                min-block-size: 44px;
+                padding: 13px 14px;
                 font-size: 13px;
                 font-weight: 600;
                 color: var(--yj-text-secondary, #b3b3b3);

frontend/src/components/explore-album-details/explore-album-details.ts

@@ -2,6 +2,7 @@ import { LitElement, html, css, nothing } from 'lit';
 import { customElement, property, state, query } from 'lit/decorators.js';
 import { classMap } from 'lit/directives/class-map.js';
 import { designTokens } from '../../styles/tokens.css';
+import { backButton } from '../../styles/back-button.css';
 import { srOnly } from '../../styles/sr-only.css';
 import { unownedLabel, unownedStyles } from '@utils/ownership';
 import {
@@ -49,9 +50,11 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
 import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import { dictByName } from '@utils/binding';
 import type { TrackDetails } from '@components/track-details/track-details.js';
@@ -327,7 +330,7 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
     @state() private ctxMenuTrack: MBTrack | null = null;
 
     @query('#track-context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
     private playlistSubmenuPopup?: WaPopup;
@@ -337,11 +340,11 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
 
     // -- ContextMenuHost interface --
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -353,6 +356,7 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
 
     static override styles = [
         designTokens,
+        backButton,
         exploreLinkStyles,
         contextMenuStyles,
         srOnly,
@@ -377,25 +381,6 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
                     var(--yj-border-subtle, rgba(255, 255, 255, 0.06));
             }
 
-            .back-button {
-                display: flex;
-                align-items: center;
-                justify-content: center;
-                width: 32px;
-                height: 32px;
-                border: none;
-                border-radius: 50%;
-                background: var(--yj-bg-overlay, rgba(255, 255, 255, 0.06));
-                color: var(--yj-text-primary, #fff);
-                cursor: pointer;
-                flex-shrink: 0;
-                transition: background-color 0.15s ease;
-            }
-
-            .back-button:hover {
-                background: var(--yj-bg-hover, rgba(255, 255, 255, 0.12));
-            }
-
             .back-button wa-icon {
                 font-size: 16px;
             }
@@ -890,6 +875,67 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
             .track-row .track-request {
                 flex-shrink: 0;
             }
+
+            /* ── The phone (#66) ──
+             *
+             * **This block is last on purpose**, for index.css's
+             * reason: a media query adds no specificity, so a rule
+             * written above the plain one it overrides loses to it and
+             * every declaration here is silently dead.
+             *
+             * Two faults, one shape. The page is a fixed header over a
+             * scrolling tracklist — the desktop arrangement — so at the
+             * reference device's 424x439 the header owned 253 of the
+             * panel's 318px and the tracklist scrolled inside the 64px
+             * that were left. And the header's flex row squeezed
+             * .album-info to 112px, so the title drew as one ellipsised
+             * glyph and two of the album's three primary actions were
+             * clipped by the host's own overflow: Shuffle album ended
+             * at x=443 in a 424px box, unreachable by any gesture.
+             *
+             * .album-info carries min-width: 0 and was shrinking as
+             * asked, so another one is not the fix — the row has to
+             * stack, or the info column has nothing to be wide with.
+             *
+             * The scroller moves to the host and .content stops being
+             * one, which is what makes the header scroll away; the
+             * tracklist is plain DOM rather than a virtualizer, so
+             * nothing inside wants a scroll window of its own. */
+            @media (max-width: 599px) {
+                :host {
+                    overflow-y: auto;
+                }
+
+                .album-header {
+                    flex-direction: column;
+                    align-items: flex-start;
+                    gap: 12px;
+                    padding: 12px 16px;
+                }
+
+                /* Stacked, the art is the whole of the header's width
+                 * budget and its 200px square is 45% of the reference
+                 * device's height. It is still what identifies the
+                 * album, so it shrinks rather than going. */
+                .cover-art-container {
+                    width: 140px;
+                    height: 140px;
+                }
+
+                /* A column flex item takes its content's width from
+                 * align-items: flex-start above, which would leave the
+                 * actions wrapping inside a box narrower than the row
+                 * they now have to themselves. */
+                .album-info {
+                    align-self: stretch;
+                }
+
+                .content {
+                    flex: 0 0 auto;
+                    overflow-y: visible;
+                    padding: 16px 16px 24px;
+                }
+            }
         `,
     ];
 
@@ -3145,10 +3191,14 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
         return html`
             ${artist
                 ? html`<div class="album-artist">
+                      <!-- keepOnPhone: the page header is not a row and
+                           has no menu of its own, so this credit is the
+                           only route from an album to its artist (#67). -->
                       ${creditLink(
                           creditStore.credits(this.releaseGroupMBID),
                           artist,
                           artistMbid,
+                          { keepOnPhone: true },
                       )}
                   </div>`
                 : nothing}
@@ -3781,11 +3831,8 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
         const track = this.ctxMenuTrack;
 
         return html`
-            <wa-popup
+            <menu-surface
                 id="track-context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu.contextMenuOpen}
             >
                 ${this.ctxMenu.contextMenuOpen && track
@@ -3846,13 +3893,12 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu.playlistSubmenuOpen}
             >
                 ${this.ctxMenu.playlistSubmenuOpen
@@ -3869,7 +3915,7 @@ export class ExploreAlbumDetails extends LitElement implements ContextMenuHost {
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 }

frontend/src/components/explore-artist-details/explore-artist-details.ts

@@ -3,6 +3,7 @@ import { LitElement, html, css, nothing } from 'lit';
 import { customElement, property, state, query } from 'lit/decorators.js';
 import { classMap } from 'lit/directives/class-map.js';
 import { designTokens } from '../../styles/tokens.css';
+import { backButton } from '../../styles/back-button.css';
 import {
     LookupArtist,
     BrowseReleaseGroups,
@@ -29,6 +30,7 @@ import { libraryStore } from '../../store/library-store';
 import { downloadStore } from '../../store/download-store';
 import '@awesome.me/webawesome/dist/components/button/button.js';
 import { trackLink, exploreLinkStyles } from '../../utils/explore-link';
+import { goToMenuItems } from '../../utils/go-to-menu';
 import { describeError } from '../../utils/describe-error';
 import {
     GetAlbumsByArtist,
@@ -61,9 +63,11 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
 import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import { dict, dictByName } from '@utils/binding';
 import type { TrackDetails } from '@components/track-details/track-details.js';
@@ -215,7 +219,7 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
     @state() private ctxMenuTarget: ContextMenuTarget | null = null;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
     private playlistSubmenuPopup?: WaPopup;
@@ -233,11 +237,11 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
 
     // -- ContextMenuHost interface --
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -264,6 +268,7 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
 
     static override styles = [
         designTokens,
+        backButton,
         exploreLinkStyles,
         contextMenuStyles,
         unownedStyles,
@@ -287,25 +292,6 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
                     var(--yj-border-subtle, rgba(255, 255, 255, 0.06));
             }
 
-            .back-button {
-                display: flex;
-                align-items: center;
-                justify-content: center;
-                width: 32px;
-                height: 32px;
-                border: none;
-                border-radius: 50%;
-                background: var(--yj-bg-overlay, rgba(255, 255, 255, 0.06));
-                color: var(--yj-text-primary, #fff);
-                cursor: pointer;
-                flex-shrink: 0;
-                transition: background-color 0.15s ease;
-            }
-
-            .back-button:hover {
-                background: var(--yj-bg-hover, rgba(255, 255, 255, 0.12));
-            }
-
             .back-button wa-icon {
                 font-size: 16px;
             }
@@ -2621,11 +2607,8 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
         const target = this.ctxMenuTarget;
 
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu.contextMenuOpen}
             >
                 ${this.ctxMenu.contextMenuOpen && target
@@ -2643,13 +2626,12 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu.playlistSubmenuOpen}
             >
                 ${this.ctxMenu.playlistSubmenuOpen
@@ -2666,7 +2648,7 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 
@@ -2724,6 +2706,16 @@ export class ExploreArtistDetails extends LitElement implements ContextMenuHost
                 <wa-icon slot="icon" name="globe"></wa-icon>
                 View on MusicBrainz
             </wa-dropdown-item>
+            <!-- The track title links to its album, and below the phone
+                 breakpoint it is plain text (#67). The artist is this
+                 page, so there is nothing to go to. -->
+            ${goToMenuItems(
+                { albumName: track.releaseName, albumMBID: track.releaseGroupMbid ?? '' },
+                {
+                    onSelect: () => this.ctxMenu.close(),
+                    onHover: () => this.ctxMenu.closePlaylistSubmenu(),
+                },
+            )}
         `;
     }
 

frontend/src/components/explore-view/explore-view.ts

@@ -23,6 +23,8 @@ import { queueStore } from '../../store/queue-store';
 import { notificationStore } from '../../store/notification-store';
 import '../notifications/inline-notice';
 import { creditLink, trackLink, exploreLinkStyles } from '../../utils/explore-link';
+import { goToMenuItems } from '../../utils/go-to-menu';
+import type { GoToTarget } from '../../utils/go-to-menu';
 import { creditStore } from '@store/credit-store';
 import { describeError } from '../../utils/describe-error';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
@@ -37,9 +39,11 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
 import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import { dict, dictByName } from '@utils/binding';
 import { ICON_QUEUE } from '@utils/icon-language';
@@ -52,10 +56,28 @@ export const ExploreRegion = 'explore';
  * is present only when owned — that's what gates the playback items,
  * while `mbid` (always present) is what "View on MusicBrainz" uses, so
  * a catalog-only card still gets a menu with somewhere useful to go.
+ *
+ * `goTo` is the names the card draws -- an artist credit, and for a
+ * recording row the release its title links to. Below the phone
+ * breakpoint those are plain text, so the menu is where they went
+ * (#67); an album card carries no album of its own, because tapping
+ * the card is already that.
  */
 type ExploreMenuTarget =
-    | { kind: 'album'; mbid: string; localId?: number; title: string }
+    | {
-    | { kind: 'recording'; mbid: string; localId?: number; title: string };
+          kind: 'album';
+          mbid: string;
+          localId?: number;
+          title: string;
+          goTo?: GoToTarget;
+      }
+    | {
+          kind: 'recording';
+          mbid: string;
+          localId?: number;
+          title: string;
+          goTo?: GoToTarget;
+      };
 type ThumbnailRequest = explore.ThumbnailRequest;
 type MBSearchResult = explore.MBSearchResult;
 type LyricsResult = explore.LyricsResult;
@@ -206,13 +228,13 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
     @state() private ctxMenuTarget: ExploreMenuTarget | null = null;
 
     @litQuery('#explore-context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     // -- ContextMenuHost interface --
     // No playlist submenu — same reason as the album/artist detail
     // pages: every action here resolves its one file lazily.
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
@@ -254,15 +276,18 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                 margin-bottom: 10px;
             }
 
+            /* 89x26 and 79x26 before this (#186). */
             .search-mode-tab {
                 display: inline-flex;
                 align-items: center;
+                justify-content: center;
                 gap: 6px;
                 background: none;
                 border: 1px solid transparent;
                 border-radius: 6px;
                 color: var(--yj-text-tertiary, #888);
                 cursor: pointer;
+                min-block-size: 44px;
                 padding: 5px 12px;
                 font-size: var(--yj-text-sm);
                 font-family: inherit;
@@ -287,7 +312,7 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                 border-radius: 6px;
                 padding: 0 12px;
                 gap: 8px;
-                height: 36px;
+                min-height: 44px;
                 max-width: 520px;
                 transition: border-color 0.15s ease;
             }
@@ -362,8 +387,15 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                 flex-shrink: 0;
             }
 
+            /* The input measured 325x**18** and the box around it 36,
+               which is two faults rather than one (#186): the row was
+               under the floor, and the input did not fill it, so eight
+               of those pixels were not a target at all. The container
+               is 44 and the input stretches to it -- a tap anywhere in
+               the box now lands on the input rather than beside it. */
             input {
                 flex: 1;
+                align-self: stretch;
                 background: none;
                 border: none;
                 outline: none;
@@ -377,15 +409,21 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                 color: var(--yj-text-tertiary, #888);
             }
 
+            /* No background until hover, so the target grows and the
+               glyph does not. It is inside a 44px box already, hence
+               the width alone. */
             .clear-button {
                 display: flex;
                 align-items: center;
                 justify-content: center;
+                align-self: stretch;
                 background: none;
                 border: none;
                 color: var(--yj-text-tertiary, #888);
                 cursor: pointer;
                 padding: 0;
+                min-inline-size: 44px;
+                margin-inline-end: -12px;
                 font-size: var(--yj-text-sm);
                 flex-shrink: 0;
             }
@@ -1341,11 +1379,8 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
         const owned = Boolean(target?.localId);
 
         return html`
-            <wa-popup
+            <menu-surface
                 id="explore-context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu.contextMenuOpen}
             >
                 ${this.ctxMenu.contextMenuOpen && target
@@ -1371,10 +1406,13 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                   <wa-icon slot="icon" name="globe"></wa-icon>
                                   View on MusicBrainz
                               </wa-dropdown-item>
+                              ${goToMenuItems(target.goTo, {
+                                  onSelect: () => this.ctxMenu.close(),
+                              })}
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 
@@ -2173,6 +2211,10 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                         mbid: rg.mbid,
                                         localId: rg.localId,
                                         title: rg.title,
+                                        goTo: {
+                                            artistName: rg.artistCredit,
+                                            artistMBID: rg.artistMbid ?? '',
+                                        },
                                     })}
                                 role="button"
                                 tabindex="0"
@@ -2185,6 +2227,10 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                             mbid: rg.mbid,
                                             localId: rg.localId,
                                             title: rg.title,
+                                            goTo: {
+                                                artistName: rg.artistCredit,
+                                                artistMBID: rg.artistMbid ?? '',
+                                            },
                                         },
                                     )}
                             >
@@ -2263,6 +2309,12 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                         mbid: r.mbid,
                                         localId: r.localId,
                                         title: r.title,
+                                        goTo: {
+                                            artistName: r.artistCredit,
+                                            artistMBID: r.artistMbid ?? '',
+                                            albumName: r.releaseName ?? '',
+                                            albumMBID: r.releaseGroupMbid ?? '',
+                                        },
                                     })}
                                 @keydown=${(e: KeyboardEvent) =>
                                     this.onCardKeydown(
@@ -2273,6 +2325,12 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                             mbid: r.mbid,
                                             localId: r.localId,
                                             title: r.title,
+                                            goTo: {
+                                                artistName: r.artistCredit,
+                                                artistMBID: r.artistMbid ?? '',
+                                                albumName: r.releaseName ?? '',
+                                                albumMBID: r.releaseGroupMbid ?? '',
+                                            },
                                         },
                                     )}
                             >

frontend/src/components/genre-details/genre-details.ts

@@ -15,6 +15,7 @@ import { describeError } from '@utils/describe-error';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@components/track-list/track-list.js';
 import { designTokens } from '../../styles/tokens.css';
+import { backButton } from '../../styles/back-button.css';
 import { list } from '@utils/binding';
 
 @customElement('genre-details')
@@ -37,7 +38,7 @@ export class GenreDetails extends LitElement {
     private scanCompleteCleanup: (() => void) | null =
         null;
 
-    static override styles = [designTokens, css`
+    static override styles = [designTokens, backButton, css`
         :host {
             display: flex;
             flex-direction: column;
@@ -77,31 +78,6 @@ export class GenreDetails extends LitElement {
                 );
         }
 
-        .back-button {
-            display: flex;
-            align-items: center;
-            justify-content: center;
-            width: 32px;
-            height: 32px;
-            border: none;
-            border-radius: 50%;
-            background: var(
-                --yj-bg-overlay,
-                rgba(255, 255, 255, 0.06)
-            );
-            color: var(--yj-text-primary, #fff);
-            cursor: pointer;
-            flex-shrink: 0;
-            transition: background-color 0.15s ease;
-        }
-
-        .back-button:hover {
-            background: var(
-                --yj-bg-hover,
-                rgba(255, 255, 255, 0.12)
-            );
-        }
-
         .back-button wa-icon {
             font-size: 16px; /* back button — outside type scale */
         }

frontend/src/components/genres-view/genres-view.ts

@@ -24,14 +24,15 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import { ViewLifecycleMixin } from '@utils/view-lifecycle';
 import { RovingGridController } from '@utils/roving-grid';
 
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@components/playlist-picker/playlist-picker.js';
 import { dictByName } from '@utils/binding';
@@ -137,19 +138,19 @@ export class GenresView
     private contextMenuGenreName: string | null = null;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     // ----- ContextMenuHost interface -----
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
     getPlaylistSubmenuPopup():
-        | WaPopup
+        | MenuTarget
         | undefined {
         return this.playlistSubmenuPopup;
     }
@@ -1176,11 +1177,8 @@ export class GenresView
 
     private renderContextMenu() {
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .contextMenuOpen}
             >
@@ -1284,13 +1282,12 @@ export class GenresView
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .playlistSubmenuOpen}
             >
@@ -1318,7 +1315,7 @@ export class GenresView
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 

frontend/src/components/home-view/home-view.ts

@@ -166,7 +166,7 @@ export class HomeView extends ViewLifecycleMixin(LitElement) {
              * gated on the device having hover rather than on width.  A
              * touch long-press synthesises a hover state in the WebView,
              * so on a phone it flashed into view during the 500ms hold
-             * that utils/long-press.ts is measuring for a context menu —
+             * that utils/touch-gestures.ts is measuring for a long press —
              * a control appearing because you were reaching for a
              * different one.  A phone user taps the album and plays from
              * the detail view, so there is nothing to replace it with.

frontend/src/components/library-filter/library-filter.ts

@@ -23,8 +23,14 @@ export class LibraryFilter extends LitElement {
             align-items: center;
         }
 
+        /* 120x32 on the reference device (#186). This control has two
+           placements since #57 -- the desktop top bar and Settings ->
+           Libraries -- and it is the only route to setSelectedLibrary
+           in either, so it is one of the controls #148 argued must not
+           simply be taken away. It is one component, so it reaches the
+           floor in one place. */
         select {
-            height: 32px;
+            min-height: 44px;
             padding: 0 8px;
             border-radius: 6px;
             border: 1px solid

frontend/src/components/menu-surface/menu-surface.ts

@@ -0,0 +1,363 @@
+/**
+ * Where a context menu is drawn: a popup on a desktop, a bottom sheet
+ * on a phone (#60).
+ *
+ * Every context menu in this app is a `.context-menu-panel` inside a
+ * `<wa-popup>` anchored to the touch point, driven by
+ * `ContextMenuController`. On the reference device that is structurally
+ * broken, and the failure was measured on the hardware rather than
+ * inferred:
+ *
+ * - Chrome 113 has **no Popover API** (`popover` is Chrome 114), so
+ *   `wa-popup` takes its own documented fallback and positions with
+ *   `strategy: "fixed"` instead of the top layer. Measured on the
+ *   device: `HTMLElement.prototype.hasOwnProperty('popover')` is false
+ *   and the popup's computed `position` is `fixed`.
+ * - `index.css` puts `contain: layout style paint` on `.main-panel`,
+ *   the ancestor of every view. Paint containment **clips** fixed
+ *   descendants. Measured: `.main-panel` computes `contain: content`
+ *   and spans 0-318 of a 439px viewport, while the open menu spans
+ *   191-401 — so 83px of it, three of its seven items, is cut off.
+ *
+ * A `<dialog>` fixes it by construction rather than by styling, because
+ * `showModal()` is Chrome 37 and uses the real top layer. **That was
+ * measured too, and it needed to be**: every other dialog in this app
+ * is mounted in `index.html`, *outside* `.main-panel`, so "dialogs are
+ * fine" was not evidence about a dialog opened from inside a view. A
+ * probe dialog appended to `track-list`'s shadow root paints to y=439,
+ * over the mini player and the tab bar, with the contained ancestor
+ * still there.
+ *
+ * Four things about this component are load-bearing.
+ *
+ * **It is one element with two presentations, not two components.**
+ * The host keeps rendering exactly the panel it rendered before and
+ * slots it into whichever surface is up, so the twelve call sites
+ * changed one tag name each and nothing else — no second item model, no
+ * second keyboard model, and `ContextMenuController` still drives
+ * `.active` and `.anchor` as if it were talking to a `wa-popup`.
+ *
+ * **Which surface exists is `matchMedia`, not a media query.** The
+ * decision is whether a `<dialog>` is in the tree at all, which is
+ * `job-band` and `player-controls`' rule: a `display: none` surface is
+ * still in the shadow root and still something a positional or by-role
+ * query finds.
+ *
+ * **The sheet has to un-do the UA stylesheet to be full-bleed.**
+ * A native `<dialog>` carries `max-width: calc(100% - 6px - 2em)` and
+ * `margin: auto`, which on the device produced a 354px panel floating
+ * in the middle of a 424px screen. `max-width: none` and explicit
+ * margins are what make it a sheet rather than a small centred box.
+ * The *positioning* needs no such care: a top-layer dialog's containing
+ * block is the viewport even with a paint-contained ancestor, which is
+ * why `bottom: 0` reaches y=439 and not the main panel's 318.
+ *
+ * **Dismissal has to travel back.** `wa-dialog` closes itself on
+ * Escape, which would otherwise leave the controller's
+ * `contextMenuOpen` true and the menu unopenable until something else
+ * cleared it. `menu-dismiss` is that signal, and the controller listens
+ * for it on the document beside the click and contextmenu listeners it
+ * already has.
+ */
+import { LitElement, css, html } from 'lit';
+import { customElement, property, query, state } from 'lit/decorators.js';
+import '@awesome.me/webawesome/dist/components/popup/popup.js';
+import '@awesome.me/webawesome/dist/components/dialog/dialog.js';
+import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+
+import { PHONE_QUERY } from '@utils/breakpoints';
+import { nameDialogsIn } from '@utils/name-dialog';
+
+/** The event a surface dispatches when it closed itself. */
+export const MENU_DISMISS_EVENT = 'menu-dismiss';
+
+/**
+ * The event a surface dispatches once it has finished showing.
+ *
+ * Only the sheet sends it, and only because `wa-dialog` moves focus to
+ * itself on the frame after `showModal()` -- see `MenuKeyboard.refocus`
+ * for why waiting longer is not the fix.
+ */
+export const MENU_SHOWN_EVENT = 'menu-shown';
+
+/**
+ * A `wa-popup` anchor: a real element or a virtual one.
+ *
+ * `undefined` rather than `null` for "not set yet", because that is
+ * what `wa-popup`'s own property accepts — this surface hands the value
+ * straight through and must not widen it.
+ */
+type MenuAnchor = WaPopup['anchor'] | undefined;
+
+/** A `wa-dialog`, as much of it as this file needs. */
+type DialogEl = HTMLElement & { open: boolean };
+
+@customElement('menu-surface')
+export class MenuSurface extends LitElement {
+    /** Whether the menu is showing. Set by `ContextMenuController`. */
+    @property({ type: Boolean }) active = false;
+
+    /**
+     * Where the popup hangs from. Ignored in sheet mode, which is
+     * anchored to the bottom of the screen rather than to the touch
+     * point — that is the whole point of a sheet.
+     */
+    @property({ attribute: false }) anchor: MenuAnchor = undefined;
+
+    /**
+     * `wa-popup`'s placement, defaulted because all twelve call sites
+     * passed the same one. Kept as a property so a future menu that
+     * wants another does not have to reach past this component.
+     */
+    @property() placement = 'bottom-start';
+
+    /**
+     * What to call the sheet, for a surface whose content is not a
+     * `.context-menu-panel` with an `aria-label` of its own -- the
+     * playlist submenu, whose content is a `playlist-picker`.
+     */
+    @property() label = '';
+
+    @state() private sheet = false;
+
+    @query('wa-popup') private popup?: WaPopup;
+
+    @query('wa-dialog') private dialog?: DialogEl;
+
+    private phoneQuery?: MediaQueryList;
+
+    static override styles = css`
+        :host {
+            display: contents;
+        }
+
+        wa-popup {
+            z-index: 200;
+        }
+
+        /* The sheet. A native dialog's UA stylesheet centres it and
+           caps its width, which on the device drew a 354px box in the
+           middle of a 424px screen — so all four of these are undoing
+           that rather than decorating. */
+        wa-dialog::part(dialog) {
+            margin: auto auto 0 auto;
+            max-width: none;
+            max-height: 85vh;
+            width: 100%;
+            border-radius: 12px 12px 0 0;
+            background: var(--yj-bg-elevated, #343a40);
+            padding: 0;
+        }
+
+        /* **A long menu scrolls; it does not hang off the bottom.**
+           Measured on the device at 80vh: seven 48px rows plus the grip
+           came to 364px against a 351px dialog, so the last row's
+           bottom was at y=452 on a 439px screen -- the one row a
+           destructive action is most likely to be. The cap has to stay
+           (a sheet covering the whole screen is a page, not a sheet),
+           so the body is what gives.
+
+           **And a body that scrolls says so** (#207). Scrolling was the
+           whole of the fix above, which left the last item reachable
+           and nothing on screen admitting it was there -- measured at
+           424x439, eight items ending at y=470 with the fold at 439,
+           and worse when the cut lands on a row boundary, where the
+           sheet ends in a clean edge that reads as the end of the list.
+
+           Two layers, and the *order* is what asks the question: a
+           shadow pinned to the bottom of the box (attachment scroll),
+           and over it a cover of the sheet's own colour painted at the
+           end of the *content* (attachment local), which therefore
+           scrolls up over the shadow and hides it exactly when there is
+           nothing more to see. So the affordance is absent on a menu
+           that fits, present the moment one does not, and gone again at
+           the end of the list -- with no scroll listener, no
+           measurement, and nothing reaching into wa-dialog's shadow
+           root for the scroller. background-attachment is Chrome 4;
+           the reference device is Chrome 113.
+
+           **The curve is steep because the rows under it stay live.**
+           A scrim over a menu item is that item's text surface, and
+           this app's rule is that text clears 4.5:1 on every surface it
+           can sit on -- which the light ramp, whose bgElevated is
+           #e9ecef, is what makes non-theoretical. A row is 48px with
+           its label centred, so 32px of scrim that is already down to
+           a quarter strength at 14px reaches y-centre at about 0.06 and
+           spends its weight on the strip below the last legible label.
+           Measured on the dark ramp at x=300, flat 52,58,64 throughout
+           before: 50,56,62 at y=330, 33,37,40 at y=350 and 22,24,27 at
+           the bottom edge, and flat again at the end of the list. The
+           light ramp puts 9.9:1 on the last label. */
+        wa-dialog::part(body) {
+            padding: 0;
+            overflow-y: auto;
+            background:
+                linear-gradient(
+                        var(--yj-bg-elevated, #343a40),
+                        var(--yj-bg-elevated, #343a40)
+                    )
+                    bottom / 100% 32px no-repeat local,
+                linear-gradient(
+                        to top,
+                        rgba(0, 0, 0, 0.6) 0%,
+                        rgba(0, 0, 0, 0.25) 45%,
+                        rgba(0, 0, 0, 0) 100%
+                    )
+                    bottom / 100% 32px no-repeat scroll;
+        }
+
+        /* A sheet is dragged at with a thumb, so it says where its top
+           edge is. Decorative: the panel below it carries the actions. */
+        .grip {
+            width: 36px;
+            height: 4px;
+            margin: 8px auto 4px;
+            border-radius: 2px;
+            background: var(--yj-text-tertiary, #888);
+        }
+    `;
+
+    override connectedCallback(): void {
+        super.connectedCallback();
+
+        // Looked up here rather than at module load, so a test can
+        // install its own matchMedia before the element is created.
+        this.phoneQuery = window.matchMedia?.(PHONE_QUERY);
+        this.sheet = this.phoneQuery?.matches ?? false;
+        this.phoneQuery?.addEventListener('change', this.onPhoneChange);
+    }
+
+    override disconnectedCallback(): void {
+        super.disconnectedCallback();
+        this.phoneQuery?.removeEventListener('change', this.onPhoneChange);
+    }
+
+    private onPhoneChange = (e: MediaQueryListEvent): void => {
+        this.sheet = e.matches;
+    };
+
+    /**
+     * Re-run the popup's positioning.
+     *
+     * Forwarded rather than dropped because `page-header` calls it when
+     * it opens the overflow menu: the popup is rendered before the
+     * button it anchors to has settled. A sheet has nothing to
+     * reposition -- it is anchored to the bottom of the screen -- so
+     * there it is deliberately a no-op rather than an error.
+     */
+    reposition(): void {
+        this.popup?.reposition();
+    }
+
+    /**
+     * The panel the host slotted in. It is light DOM here and stays in
+     * the host's shadow root, which is what keeps the host's own
+     * `contextMenuStyles` applying to it in both presentations.
+     */
+    private get panel(): HTMLElement | null {
+        return this.querySelector('.context-menu-panel');
+    }
+
+    override updated(): void {
+        const panel = this.panel;
+
+        // The sheet's rows are bigger, and that rule lives in the one
+        // stylesheet every call site already includes rather than in
+        // twelve places. The attribute is how it knows.
+        if (panel) panel.toggleAttribute('data-sheet', this.sheet);
+
+        if (this.sheet) {
+            this.syncSheet(panel);
+
+            return;
+        }
+
+        if (this.popup) {
+            if (this.anchor) this.popup.anchor = this.anchor;
+
+            this.popup.active = this.active;
+        }
+    }
+
+    private syncSheet(panel: HTMLElement | null): void {
+        const dialog = this.dialog;
+
+        if (!dialog) return;
+
+        // The dialog is named after the menu it contains, so no call
+        // site has to say the same thing twice: the panel already
+        // carries `role="menu"` and an `aria-label` naming what it acts
+        // on. `without-header` renders no heading, which is
+        // `name-dialog`'s documented `aria-label` path.
+        const label = panel?.getAttribute('aria-label') || this.label;
+
+        if (label) dialog.setAttribute('label', label);
+
+        nameDialogsIn(this.shadowRoot);
+
+        if (dialog.open !== this.active) dialog.open = this.active;
+    }
+
+    /**
+     * `wa-dialog` closed itself — Escape, or its own close button.
+     * The controller owns `contextMenuOpen`, so it has to hear about
+     * it or the menu is left open in state and shut on screen.
+     */
+    private onDialogShown = (): void => {
+        if (!this.active) return;
+
+        this.dispatchEvent(
+            new CustomEvent(MENU_SHOWN_EVENT, {
+                bubbles: true,
+                composed: true,
+            }),
+        );
+    };
+
+    private onDialogHide = (): void => {
+        if (!this.active) return;
+
+        this.dispatchEvent(
+            new CustomEvent(MENU_DISMISS_EVENT, {
+                bubbles: true,
+                composed: true,
+            }),
+        );
+    };
+
+    override render() {
+        if (this.sheet) {
+            // **The anchor stays out of the sheet.** One call site --
+            // `page-header`'s overflow menu -- slots its own trigger
+            // button as the thing the popup hangs from, and a sheet
+            // hangs from the bottom of the screen instead. Rendering
+            // that slot outside the dialog is what keeps the button on
+            // the page rather than inside the surface it opens.
+            return html`
+                <slot name="anchor"></slot>
+                <wa-dialog
+                    without-header
+                    data-testid="menu-sheet"
+                    @wa-after-show=${this.onDialogShown}
+                    @wa-hide=${this.onDialogHide}
+                >
+                    <div class="grip"></div>
+                    <slot></slot>
+                </wa-dialog>
+            `;
+        }
+
+        return html`
+            <wa-popup placement=${this.placement} flip shift>
+                <slot name="anchor" slot="anchor"></slot>
+                <slot></slot>
+            </wa-popup>
+        `;
+    }
+}
+
+declare global {
+    interface HTMLElementTagNameMap {
+        'menu-surface': MenuSurface;
+    }
+}

frontend/src/components/now-playing-view/now-playing-view.ts

@@ -105,6 +105,19 @@ export class NowPlayingView extends LitElement {
             color: var(--yj-text-secondary, #adb5bd);
         }
 
+        /* The art and the names are one block, so that a short
+           screen can lay them out side by side without either of them
+           knowing about the other's box. Vertically it is exactly what
+           the host used to do -- same gap, art flexible, names fixed --
+           so the tall layout is unchanged. */
+        .stack {
+            display: flex;
+            flex-direction: column;
+            gap: 0.75em;
+            flex: 1 1 auto;
+            min-height: 0;
+        }
+
         .art {
             flex: 1 1 auto;
             display: flex;
@@ -113,19 +126,89 @@ export class NowPlayingView extends LitElement {
             min-height: 0;
         }
 
-        .art img,
+        .art img {
-        .art .placeholder {
+            /* Square, and never larger than the room left over --
-            /* Square, and never taller than the room left over: the
+               where "square" is a property of what is painted and not
-               art is the one thing here that would happily push the
+               just of what was asked for.
-               transport off the bottom of a short phone. */
+
-            width: min(100%, 60vh);
+               The previous rule asked for a square and did not get
+               one. width: min(100%, 60vh) makes the width definite,
+               aspect-ratio: 1 derives the height from it, and
+               max-height: 100% then clamps that height **without
+               re-deriving the width** -- which is how the
+               aspect-ratio property is specified to behave, unlike
+               an intrinsic ratio. So whenever the room left over was
+               shorter than the box was wide, the art was drawn as a
+               letterbox strip and object-fit: cover cropped the
+               cover to it. Measured on the reference device at
+               424x439: **264x53**, a 5:1 band of a square image.
+
+               That is not only the phone. The leftover exceeds the
+               width only above ~843px of viewport, so every height
+               from ~500 to ~843 -- most phones, and any small window
+               -- drew a cropped strip too.
+
+               Both maxes with auto sizes is the fix, and it is the
+               replaced-element path rather than the aspect-ratio
+               one: the used size preserves the ratio under *both*
+               bounds (CSS2.1 10.4), so the art is square at every
+               height. Checked against Chrome 113 itself -- the
+               device's engine -- at column heights of 288, 300, 451,
+               600 and 800: square at all five, where the old rule
+               cropped at four.
+
+               A corollary worth knowing: auto will not upscale past
+               the image's natural size, and the largest tier
+               saveCoverArt keeps is 400px. Drawing it larger was
+               upscaling, so nothing is lost. */
+            max-width: 100%;
+            max-height: 100%;
+            width: auto;
+            height: auto;
             aspect-ratio: 1;
             object-fit: cover;
             border-radius: 12px;
             background-color: var(--yj-bg-elevated, #343a40);
         }
 
+        /* The placeholder is not a replaced element, so it cannot use
+           the rule above: with no intrinsic size, auto/auto collapses
+           it to its icon -- measured at 13x58 in Chrome 113, which is
+           neither square nor the art's size.
+
+           So it is sized from the height, and then bounded by the
+           width in the one way a box like this can be. A non-replaced
+           element cannot express "the largest square that fits" in a
+           single rule: aspect-ratio derives the second axis from the
+           first, and whichever max clamps it does not re-derive the
+           other, which is the same trap the image rule above is about.
+           Driving it from the height alone is right until the column
+           is taller than it is wide -- ~843px of viewport, which is a
+           tall phone and #51's other named device -- and there it went
+           380x484.
+
+           max-height in viewport units is what closes it, and it is
+           sound here for the reason 60vh was not: this view is a
+           phone-width detail view, so its content box really is the
+           viewport less the host's own 1rem gutters. It is a *max*, so
+           the failure mode if that ever stopped being true is a square
+           bounded slightly early rather than a crop. rem and not em --
+           this box sets font-size: 3rem for the icon, so 2em here
+           would be 96px. */
         .art .placeholder {
+            height: 100%;
+            width: auto;
+            max-width: 100%;
+            max-height: calc(100vw - 2rem);
+            /* A flex item's automatic minimum is its content, so
+               without this the icon's own width becomes a floor and
+               the box goes wider than it is tall the moment the row is
+               shorter than the icon -- which is exactly the state a
+               job band puts this screen in. */
+            min-width: 0;
+            aspect-ratio: 1;
+            border-radius: 12px;
+            background-color: var(--yj-bg-elevated, #343a40);
             display: flex;
             align-items: center;
             justify-content: center;
@@ -213,6 +296,60 @@ export class NowPlayingView extends LitElement {
             color: var(--yj-text-secondary, #adb5bd);
             text-align: center;
         }
+
+        /* Below 500px of viewport the art and the names sit side by
+           side, and that is the whole of this screen's answer to a
+           short phone (#51).
+
+           The stacked layout cannot be rescued by sizing alone. Its
+           budget is fixed -- 48px of header, 143px of transport since
+           #64, 78px of names, 68px of padding and gaps -- so the art
+           gets height - 386, which on the reference device's 424x439
+           is **53px**. #172 measured 39px before #64 and named the
+           two options: give the art a floor and let the block scroll,
+           or reflow. A floor scrolls the transport off the bottom,
+           and "controls never scroll off" is #51's own Direction and
+           plan 018's promise -- so it is the reflow.
+
+           Sideways the art is bounded by the row's height rather than
+           by the column's leftover, which is the whole gain: the same
+           439px screen goes from a 53px sliver to **143px**, measured
+           on the device, with nothing scrolling and the transport
+           untouched.
+
+           500 is where the two layouts cross rather than a round
+           number. In a row the art is height - 296 and the names get
+           what is left of 392px, so the names hold 176px at exactly
+           500 and less above it; stacked, the art is height - 386,
+           which passes 176px at 562. Below 500 the row is the bigger
+           art *and* the readable one -- above it the column is, which
+           is why a tall phone (a Pixel 7's ~869) keeps the layout it
+           has. Unverified on that device: none was attached.
+
+           It is keyed on height alone, not on the phone's width,
+           because it is an answer to vertical room -- a 900x450 window
+           has the same problem and the same fix. */
+        @media (max-height: 500px) {
+            .stack {
+                flex-direction: row;
+                align-items: center;
+            }
+
+            /* A square of the row's height. The box has to carry the
+               ratio here rather than the image, because in a row the
+               art's width is what the ratio has to produce -- and the
+               image's own rule then fits it to a box that is already
+               square. */
+            .art {
+                flex: 0 1 auto;
+                height: 100%;
+                aspect-ratio: 1;
+            }
+
+            .meta {
+                flex: 1 1 auto;
+            }
+        }
     `];
 
     private back() {
@@ -264,60 +401,84 @@ export class NowPlayingView extends LitElement {
         return html`
             ${this.renderHeader()}
 
-            <div class="art">
+            <div class="stack">
-                ${art
+                <div class="art">
-                    ? html`<img
+                    ${art
-                          src=${art}
+                        ? html`<img
-                          alt=""
+                              src=${art}
-                          decoding="async"
+                              alt=""
-                          data-testid="npv-art"
+                              decoding="async"
-                      />`
+                              data-testid="npv-art"
-                    : html`<div class="placeholder" aria-hidden="true">
+                          />`
-                          <wa-icon name="compact-disc"></wa-icon>
+                        : html`<div class="placeholder" aria-hidden="true">
-                      </div>`}
+                              <wa-icon name="compact-disc"></wa-icon>
-            </div>
+                          </div>`}
-
-            <div class="meta">
-                <div class="names">
-                    <h2 class="title" data-testid="npv-title">
-                        ${track.title || track.fileName}
-                    </h2>
-                    <p class="artist">
-                        ${creditLink(
-                            creditStore.credits(track.recordingMbid),
-                            track.artist,
-                            track.artistMbid,
-                        )}
-                    </p>
-                    ${track.album
-                        ? html`<p class="album">
-                              ${albumLink(
-                                  track.album,
-                                  track.releaseGroupMbid,
-                                  undefined,
-                                  track.artist,
-                              )}
-                          </p>`
-                        : nothing}
                 </div>
 
-                <button
+                <div class="meta">
-                    type="button"
+                    <div class="names">
-                    class="favorite ${favorited ? 'on' : ''}"
+                        <h2 class="title" data-testid="npv-title">
-                    data-testid="npv-favorite"
+                            ${track.title || track.fileName}
-                    aria-pressed=${favorited ? 'true' : 'false'}
+                        </h2>
-                    aria-label=${favorited
+                        <!-- keepOnPhone: this screen is the phone's,
-                        ? `Remove ${track.title} from ${this.favCtrl.playlistName}`
+                             and it has no context menu to carry the
-                        : `Add ${track.title} to ${this.favCtrl.playlistName}`}
+                             destination the way a row does (#67).
-                    @click=${this.toggleFavorite}
+                             Suppressing these takes the artist and the
-                >
+                             album away rather than moving them, and
-                    <wa-icon name=${this.favCtrl.iconFor(favorited)}></wa-icon>
+                             they are two lines of their own here
-                </button>
+                             rather than a few characters inside a
+                             row. -->
+                        <p class="artist">
+                            ${creditLink(
+                                creditStore.credits(track.recordingMbid),
+                                track.artist,
+                                track.artistMbid,
+                                { keepOnPhone: true },
+                            )}
+                        </p>
+                        ${track.album
+                            ? html`<p class="album">
+                                  ${albumLink(
+                                      track.album,
+                                      track.releaseGroupMbid,
+                                      undefined,
+                                      track.artist,
+                                      { keepOnPhone: true },
+                                  )}
+                              </p>`
+                            : nothing}
+                    </div>
+
+                    <button
+                        type="button"
+                        class="favorite ${favorited ? 'on' : ''}"
+                        data-testid="npv-favorite"
+                        aria-pressed=${favorited ? 'true' : 'false'}
+                        aria-label=${favorited
+                            ? `Remove ${track.title} from ${this.favCtrl.playlistName}`
+                            : `Add ${track.title} to ${this.favCtrl.playlistName}`}
+                        @click=${this.toggleFavorite}
+                    >
+                        <wa-icon name=${this.favCtrl.iconFor(favorited)}></wa-icon>
+                    </button>
+                </div>
             </div>
 
             <div class="transport">
                 <seek-bar></seek-bar>
-                <player-controls></player-controls>
+                <!-- context="full": this view *is* the player, so the
+                     transport is the page rather than a strip of it --
+                     primary controls large, shuffle and repeat beneath
+                     at normal size (#56). It is a property rather than
+                     a media query because the bottom bar wants a
+                     different answer at this same viewport. -->
+                <player-controls context="full"></player-controls>
+                <!-- Rendered unconditionally and absent on its own
+                     terms where the device owns the volume (#64): the
+                     control asks the player, not this view and not the
+                     viewport. A hidden host draws no gap, so that is
+                     29px of a 439px screen back to the album art
+                     (#172). -->
                 <volume-control></volume-control>
             </div>
         `;

frontend/src/components/now-playing/now-playing.ts

@@ -215,6 +215,17 @@ export class NowPlaying extends LitElement {
         outline: 2px solid var(--yj-accent, #ffd43b);
         outline-offset: 2px;
       }
+
+      /* The favourite is one of the three controls #59 keeps on the
+         phone's bar, and it was the **smallest control in the app**:
+         measured at 424x439, 18x14px, against the 48x48 art beside it.
+         Zero padding around an icon-sized glyph is a reasonable mouse
+         target and is not a thumb target at all. */
+      .fav-btn {
+        min-width: 44px;
+        min-height: 44px;
+        font-size: var(--yj-icon-md);
+      }
     }
 
     .cover-preview-panel {
@@ -446,8 +457,30 @@ export class NowPlaying extends LitElement {
             return html`
         <div class="sr-only" role="status" aria-live="polite">${announcement}</div>
         <div class="now-playing">
-          <div class="cover-art">
+          <!-- **The way to Now Playing does not depend on what is
-            <div class="cover-placeholder"><wa-icon name="music"></wa-icon></div>
+               playing.** This branch used to render the placeholder
+               with no button on it, so on a phone there was no route to
+               the full-screen view while nothing was loaded -- and once
+               #59 took the queue button off the bar, that made the
+               queue itself unreachable, because Now Playing is where it
+               is reached from. The queue is persisted across restarts,
+               so "a queue with tracks in it and nothing playing" is an
+               ordinary state to launch into, not a corner.
+
+               Plan 018's matrix promises no action is unreachable at
+               any supported size, and the promise is what makes #59
+               allowed to remove a control at all. -->
+          <div class="cover-art-wrapper">
+            <button
+              type="button"
+              class="expand"
+              data-testid="open-now-playing"
+              aria-label="Open now playing"
+              @click=${this.openNowPlaying}
+            ></button>
+            <div class="cover-art">
+              <div class="cover-placeholder"><wa-icon name="music"></wa-icon></div>
+            </div>
           </div>
         </div>
         <div

frontend/src/components/page-header/page-header.ts

@@ -1,9 +1,9 @@
 import { LitElement, html, css, nothing } from 'lit';
 import { customElement, property, query, state } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
-import '@awesome.me/webawesome/dist/components/popup/popup.js';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 
 import { designTokens } from '../../styles/tokens.css';
 import {
@@ -183,8 +183,8 @@ export class PageHeader extends LitElement {
     @query('#page-header-overflow')
     private menuPanel?: HTMLElement;
 
-    @query('wa-popup')
+    @query('menu-surface')
-    private popup?: WaPopup;
+    private popup?: MenuSurface;
 
     private menuKeyboard = new MenuKeyboard(() => this.closeMenu());
 
@@ -298,6 +298,47 @@ export class PageHeader extends LitElement {
                 flex-shrink: 0;
             }
 
+            /* Every control in this header meets the app's 44px touch
+               floor -- the number #56 set for the transport and the
+               queue header already keeps (#186).
+
+               It is min-size rather than padding with a negative
+               margin, which is what the seek bar needed (#187), and
+               the difference is worth stating because it decides
+               whether targets can collide. There the painted track had
+               to stay thin, so the target was grown past its own box
+               and had to be checked against its neighbours. Here the
+               control *is* the target: the boxes are flex items, so
+               the gap keeps them apart and no two can overlap by
+               construction.
+
+               There is no phone branch. With the target being the box,
+               a 44px control on a desktop is merely large, and a
+               second declaration of what a phone shows is a second
+               thing to keep in step -- which is the reason this
+               component has never had one. It also avoids a media
+               query that no tier here renders, which is exactly how
+               the seek bar's phone rule came to be dead for months.
+
+               **The height is the box and the width is not**, and that
+               asymmetry is the whole of what the overflow fit below
+               cares about. That pass measures inline size, so a taller
+               control costs it nothing and a wider one costs it
+               directly. Growing the two square controls to 44px wide
+               added 22px, which fits at every width Chromium was
+               checked at and clipped the overflow trigger at 320px in
+               **WebKit** -- the engine closest to what actually ships,
+               and the one no machine here can run. So the horizontal
+               half is padding with the margin cancelling it, which is
+               what the issue asked for in the first place: the target
+               grows and the layout does not.
+
+               The cost is that a horizontal target can now overlap a
+               neighbour, which the box version could not. The arrow's
+               is deliberately lopsided for the seek bar's reason
+               (#187): the select is 6px to its left and there is open
+               space to its right, so it takes the side with nothing to
+               steal from. */
             .sort select {
                 font: inherit;
                 color: inherit;
@@ -306,6 +347,7 @@ export class PageHeader extends LitElement {
                 border-radius: 4px;
                 padding: 3px 6px;
                 cursor: pointer;
+                min-block-size: 44px;
             }
 
             .sort-dir {
@@ -318,6 +360,18 @@ export class PageHeader extends LitElement {
                 color: inherit;
                 cursor: pointer;
                 padding: 3px 5px;
+                /* 28x21 before this, the smallest control in the
+                   header and the only one that failed the floor in
+                   both directions.
+
+                   Vertically the box grows, because the header has the
+                   room and nothing measures it. Horizontally the box
+                   must not: 28 + 2 + 14 is a 44px target over a 28px
+                   layout box, weighted right because the select is 6px
+                   to the left. */
+                min-block-size: 44px;
+                padding-inline: 5px 21px;
+                margin-inline: 0 -16px;
             }
 
             .sort-dir:hover {
@@ -377,10 +431,20 @@ export class PageHeader extends LitElement {
                 gap: 6px;
                 white-space: nowrap;
                 flex-shrink: 0;
+                justify-content: center;
+                min-block-size: 44px;
             }
 
             .more-button {
                 padding: 6px 10px;
+                /* 38x27, and it is the route to every collapsed
+                   action, so it is the last control that should be
+                   hard to hit -- and the one WebKit clipped at 320px
+                   when this was 6px wider as a box. 38 + 3 + 3 is a
+                   44px target over a 38px layout box; the actions row
+                   has an 8px gap, so this one can be symmetric. */
+                padding-inline: 13px;
+                margin-inline: -3px;
             }
 
             /* The display: flex above outranks the UA stylesheet's
@@ -418,7 +482,7 @@ export class PageHeader extends LitElement {
                 outline-offset: -1px;
             }
 
-            wa-popup {
+            menu-surface {
                 z-index: 200;
             }
 
@@ -670,10 +734,17 @@ export class PageHeader extends LitElement {
         return html`
             <div class="actions">
                 ${this.actions.map((a) => this.renderActionButton(a))}
-                <wa-popup
+                <!-- A sheet below 600px, like every other menu in the
+                     app (#60). The clipping that issue is about does
+                     not bite here — this one opens downward from the
+                     top of a full-height view, so it has somewhere to
+                     go even without top-layer promotion — but the touch
+                     targets do: on a phone *every* action of a page
+                     that overflows lives in here, at wa-dropdown-item
+                     defaults. One surface, so there is no second
+                     answer to what a menu looks like. -->
+                <menu-surface
                     placement="bottom-end"
-                    flip
-                    shift
                     .active=${this.menuOpen}
                 >
                     <button
@@ -711,7 +782,7 @@ export class PageHeader extends LitElement {
                             `,
                         )}
                     </div>
-                </wa-popup>
+                </menu-surface>
             </div>
         `;
     }

frontend/src/components/playlist-details/playlist-details.ts

@@ -7,7 +7,8 @@ import {
 } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@lit-labs/virtualizer';
 import type { LitVirtualizer } from '@lit-labs/virtualizer';
@@ -35,8 +36,12 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { focusRovingRow, nextRovingIndex } from '@utils/roving-rows';
+import type { GestureEvent } from '@utils/touch-gestures';
+import { SwipeToQueue, swipeRevealStyles } from '@utils/swipe-to-queue';
+import '@components/selection-bar/selection-bar';
+import type { SelectionAction } from '@components/selection-bar/selection-bar';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import { notificationStore } from '@store/notification-store';
 import { describeError } from '@utils/describe-error';
@@ -69,11 +74,17 @@ import {
     trackLink,
     exploreLinkStyles,
 } from '@utils/explore-link';
+import { goToMenuItems } from '@utils/go-to-menu';
+import type { GoToTarget } from '@utils/go-to-menu';
 import { designTokens } from '../../styles/tokens.css';
+import { srOnly } from '../../styles/sr-only.css';
+import { backButton } from '../../styles/back-button.css';
 import { list } from '@utils/binding';
 import {
+    ICON_PLAY,
     ICON_PLAYLIST,
     ICON_QUEUE,
+    ICON_REMOVE,
 } from '@utils/icon-language';
 
 /** One playlist row: the track and its position in the *playlist*,
@@ -145,10 +156,10 @@ export class PlaylistDetails
     private dragImageEl: HTMLElement | null = null;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     @query('track-details')
     private trackDetailsDialog!: TrackDetails;
@@ -163,11 +174,11 @@ export class PlaylistDetails
     // ContextMenuHost interface
     // =================================================================
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -420,6 +431,127 @@ export class PlaylistDetails
         queueStore.setQueue(filePaths, trackIndex, false, { type: 'playlist', id: this.playlistId, label: this.playlistName });
     }
 
+    // =================================================================
+    // A finger on a playlist row (plan 019 phase 3, #63)
+    // =================================================================
+
+    /** The row an announced gesture is on, with its track. */
+    private rowFromGesture(
+        e: Event,
+    ): { index: number; track: playlist.Track } | null {
+        const row = (e.target as HTMLElement).closest(
+            '.track-item',
+        ) as HTMLElement | null;
+
+        if (!row) return null;
+
+        const index = Number(row.dataset.index);
+        const track = this.tracks[index];
+
+        if (Number.isNaN(index) || !track) return null;
+
+        return { index, track };
+    }
+
+    /**
+     * A tap plays the playlist from that row.
+     *
+     * The same thing a double-click does, which is the rule the whole
+     * app follows: activating one row plays the list the row is in,
+     * from that row, rather than a queue of one that stops when the
+     * song ends.
+     */
+    private onRowTap = (e: GestureEvent) => {
+        const hit = this.rowFromGesture(e);
+
+        if (!hit) return;
+
+        if (this.selection.selectionMode) {
+            e.preventDefault();
+            this.focusedIndex = hit.index;
+            this.selection.toggleInMode(String(hit.index), hit.index);
+            this.virtualizer?.requestUpdate();
+
+            return;
+        }
+
+        // A missing file has nothing to play, so the tap is left
+        // unclaimed and falls through to the click that selects it --
+        // which is what a mouse does here and the only useful thing a
+        // phantom row can answer.
+        if (hit.track.Phantom) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+        this.handleTrackDblClick(hit.index);
+    };
+
+    private onRowLongPress = (e: GestureEvent) => {
+        const hit = this.rowFromGesture(e);
+
+        if (!hit) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+        this.selection.enterSelectionMode(String(hit.index), hit.index);
+        this.virtualizer?.requestUpdate();
+    };
+
+    /**
+     * Swipe a row right to queue it.
+     *
+     * `track-list`'s rule, one list over: one row is a position and
+     * several rows are an explicit choice, and a swipe never changes
+     * the selection it reads.
+     */
+    private swipe = new SwipeToQueue(this, {
+        resolve: (e) => {
+            const hit = this.rowFromGesture(e);
+
+            // A phantom has no file to queue, so there is nothing for
+            // the reveal to promise.
+            if (!hit || hit.track.Phantom) return null;
+
+            const selected = this.selection.getSelectedIndices();
+            const many =
+                selected.length > 1 && selected.includes(hit.index);
+            const filePaths = many
+                ? this.getSelectedFilePaths()
+                : [hit.track.FilePath];
+
+            return { index: hit.index, filePaths, label: hit.track.Title };
+        },
+        repaint: () => this.virtualizer?.requestUpdate(),
+    });
+
+    /** The three worth a thumb; the sheet behind "More" is the rest. */
+    private static readonly SELECTION_ACTIONS: SelectionAction[] = [
+        { id: 'play', label: 'Play', icon: ICON_PLAY },
+        { id: 'add-to-queue', label: 'Add to queue', icon: ICON_QUEUE },
+        { id: 'remove', label: 'Remove', icon: ICON_REMOVE, danger: true },
+    ];
+
+    private renderSelectionBar() {
+        if (!this.selection.selectionMode) return nothing;
+
+        return html`
+            <selection-bar
+                .count=${this.selection.selectionCount}
+                .actions=${PlaylistDetails.SELECTION_ACTIONS}
+                @selection-exit=${this.onSelectionExit}
+                @selection-action=${(e: CustomEvent<{ id: string }>) =>
+                this.onContextMenuAction(e.detail.id)}
+                @selection-more=${(e: CustomEvent<{ x: number; y: number }>) =>
+                this.ctxMenu.openAt(e.detail.x, e.detail.y)}
+            ></selection-bar>
+        `;
+    }
+
+    private onSelectionExit = () => {
+        this.selection.exitSelectionMode();
+        this.virtualizer?.requestUpdate();
+    };
+
     private handleTrackContextMenu(
         e: MouseEvent,
         trackIndex: number,
@@ -459,6 +591,28 @@ export class PlaylistDetails
             .map((i) => this.tracks[i]!.FilePath);
     }
 
+    /**
+     * The row "Go to Artist" / "Go to Album" navigate from — one row
+     * or none, and only below the phone breakpoint, where the row's
+     * own names stopped being links (#67).
+     */
+    private get goToTarget(): GoToTarget | undefined {
+        const indices = this.selection.getSelectedIndices();
+
+        if (indices.length !== 1) return undefined;
+
+        const track = this.tracks[indices[0]!];
+
+        if (!track) return undefined;
+
+        return {
+            artistName: track.Artist,
+            artistMBID: track.ArtistMBID,
+            albumName: track.Album,
+            albumMBID: track.ReleaseGroupMBID,
+        };
+    }
+
     // =================================================================
     // Context menu actions
     // =================================================================
@@ -953,8 +1107,11 @@ export class PlaylistDetails
 
     static override styles = [
         designTokens,
+        srOnly,
+        backButton,
         contextMenuStyles,
         exploreLinkStyles,
+        swipeRevealStyles,
         css`
         :host {
             display: flex;
@@ -980,31 +1137,6 @@ export class PlaylistDetails
                 );
         }
 
-        .back-button {
-            display: flex;
-            align-items: center;
-            justify-content: center;
-            width: 32px;
-            height: 32px;
-            border: none;
-            border-radius: 50%;
-            background: var(
-                --yj-bg-overlay,
-                rgba(255, 255, 255, 0.06)
-            );
-            color: var(--yj-text-primary, #fff);
-            cursor: pointer;
-            flex-shrink: 0;
-            transition: background-color 0.15s ease;
-        }
-
-        .back-button:hover {
-            background: var(
-                --yj-bg-hover,
-                rgba(255, 255, 255, 0.12)
-            );
-        }
-
         .back-button wa-icon {
             font-size: 16px;
         }
@@ -1158,6 +1290,9 @@ export class PlaylistDetails
         .track-item {
             width: 100%;
             box-sizing: border-box;
+            /* The swipe reveal is absolute inside the row. */
+            position: relative;
+            overflow: hidden;
         }
 
         .track-header {
@@ -1222,8 +1357,14 @@ export class PlaylistDetails
             user-select: none;
         }
 
-        .track-item:hover {
+        /* A hover tint is for a device that hovers (#54). A hold
-            background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+           synthesises a hover in the WebView, so ungated this arrives
+           because a finger touched the row and stays after it has
+           gone; the press state below is what a tap gets instead. */
+        @media (hover: hover) and (pointer: fine) {
+            .track-item:hover {
+                background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+            }
         }
 
         .track-item.selected {
@@ -1243,11 +1384,13 @@ export class PlaylistDetails
             cursor: pointer;
         }
 
-        .track-item.phantom:hover {
+        @media (hover: hover) and (pointer: fine) {
-            background-color: var(
+            .track-item.phantom:hover {
-                --yj-hover-overlay,
+                background-color: var(
-                rgba(255, 255, 255, 0.05)
+                    --yj-hover-overlay,
-            );
+                    rgba(255, 255, 255, 0.05)
+                );
+            }
         }
 
         .track-item.phantom.selected {
@@ -1257,6 +1400,19 @@ export class PlaylistDetails
             );
         }
 
+        /* The press state (#54): the feedback a tap has now that the
+           web view's own highlight box is gone (index.css). Last, and
+           carrying a class, because a selected or playing row is two
+           classes deep and a bare :active would lose to it. */
+        .track-item.selected:active,
+        .track-item.active:active,
+        .track-item:active {
+            background-color: var(
+                --yj-press-overlay,
+                rgba(255, 255, 255, 0.12)
+            );
+        }
+
         .phantom-row {
             grid-column: 1 / -1;
             display: flex;
@@ -1455,6 +1611,9 @@ export class PlaylistDetails
                 <div class="header-cell col-album">Album</div>
                 <div class="header-cell col-duration">Duration</div>
             </div>
+            <div class="sr-only" role="status" aria-live="polite">
+                ${this.swipe.announcement}
+            </div>
             <lit-virtualizer
                 class="track-scroller"
                 role="listbox"
@@ -1464,7 +1623,13 @@ export class PlaylistDetails
                 .renderItem=${this.renderRow}
                 .keyFunction=${this.rowKey}
                 .layout=${this.flowLayout}
+                @yj-tap=${this.onRowTap}
+                @yj-long-press=${this.onRowLongPress}
+                @yj-swipe-start=${this.swipe.onSwipeStart}
+                @yj-swipe-move=${this.swipe.onSwipeMove}
+                @yj-swipe-end=${this.swipe.onSwipeEnd}
             ></lit-virtualizer>
+            ${this.renderSelectionBar()}
         `;
     }
 
@@ -1486,6 +1651,7 @@ export class PlaylistDetails
                         active ? 'active' : '',
                         selected ? 'selected' : '',
                         isPhantom ? 'phantom' : '',
+                        this.swipe.isSwiping(trackIndex) ? 'swiping' : '',
                     ]
                         .filter(Boolean)
                         .join(' ');
@@ -1496,6 +1662,7 @@ export class PlaylistDetails
                             role="option"
                             aria-selected=${selected}
                             data-index=${trackIndex}
+                            data-swipe
                             tabindex=${trackIndex === this.focusedIndex ? 0 : -1}
                             @keydown=${(e: KeyboardEvent) =>
                                 this.onRowKeydown(e, trackIndex)}
@@ -1542,6 +1709,7 @@ export class PlaylistDetails
                                 ? nothing
                                 : this.onTrackDragEnd}
                         >
+                            ${this.swipe.renderReveal(trackIndex)}
                             ${isPhantom
                                 ? html`<div
                                       class="phantom-row"
@@ -1617,11 +1785,8 @@ export class PlaylistDetails
 
     private renderContextMenu() {
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .contextMenuOpen}
             >
@@ -1780,16 +1945,23 @@ export class PlaylistDetails
                                       Track
                                       Details
                                   </wa-dropdown-item>
+                                  ${goToMenuItems(this.goToTarget, {
+                                      onSelect: () => {
+                                          this.selection.clear();
+                                          this.ctxMenu.close();
+                                      },
+                                      onHover: () =>
+                                          this.ctxMenu.closePlaylistSubmenu(),
+                                  })}
                               </div>
                           `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .playlistSubmenuOpen}
             >
@@ -1816,7 +1988,7 @@ export class PlaylistDetails
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 }

frontend/src/components/playlist-view/playlist-view.ts

@@ -2,7 +2,9 @@ import { LitElement, html, css, nothing } from 'lit';
 import { customElement, state, query } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 
 import {
@@ -140,7 +142,7 @@ export class PlaylistView extends ViewLifecycleMixin(LitElement) {
     private pendingDropPaths: string[] = [];
 
     @query('#playlist-context-menu')
-    private playlistContextMenuPopup!: WaPopup;
+    private playlistContextMenuPopup!: MenuSurface;
 
     @query('duplicate-tracks-dialog')
     private duplicateDialog!: DuplicateTracksDialog;
@@ -1059,7 +1061,7 @@ export class PlaylistView extends ViewLifecycleMixin(LitElement) {
         );
     }
 
-    private closePlaylistContextMenu() {
+    private closePlaylistContextMenu = () => {
         if (!this.playlistContextMenuOpen) return;
 
         this.menuKeyboard.close();
@@ -1072,7 +1074,7 @@ export class PlaylistView extends ViewLifecycleMixin(LitElement) {
         if (popup) {
             popup.active = false;
         }
-    }
+    };
 
     private async onPlaylistContextAction(
         action: string,
@@ -1500,13 +1502,11 @@ export class PlaylistView extends ViewLifecycleMixin(LitElement) {
                   </div>`
                 : this.renderPlaylistList()}
 
-            <wa-popup
+            <menu-surface
                 id="playlist-context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this
                     .playlistContextMenuOpen}
+                @menu-dismiss=${this.closePlaylistContextMenu}
             >
                 ${this.playlistContextMenuOpen
                     ? html`
@@ -1564,7 +1564,7 @@ export class PlaylistView extends ViewLifecycleMixin(LitElement) {
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
             <duplicate-tracks-dialog
                 @playlist-action-complete=${() =>

frontend/src/components/queue-panel/queue-panel.ts

@@ -9,9 +9,11 @@ import {
 } from 'lit/decorators.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import { QueueController } from '@store/controllers/queue-controller';
+import { PHONE_QUERY } from '@utils/breakpoints';
 import { creditStore } from '@store/credit-store';
 import {
     describeQueueSource,
@@ -34,7 +36,7 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { focusRovingRow, nextRovingIndex } from '@utils/roving-rows';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import {
@@ -60,11 +62,18 @@ import {
     trackLink,
     exploreLinkStyles,
 } from '@utils/explore-link';
+import { goToMenuItems } from '@utils/go-to-menu';
+import type { GoToTarget } from '@utils/go-to-menu';
 import {
     ICON_NEW,
+    ICON_PLAY,
     ICON_PLAYLIST,
     ICON_QUEUE,
+    ICON_REMOVE,
 } from '@utils/icon-language';
+import type { GestureEvent } from '@utils/touch-gestures';
+import '@components/selection-bar/selection-bar';
+import type { SelectionAction } from '@components/selection-bar/selection-bar';
 /** Above this many tracks, clearing the queue asks first. */
 const CLEAR_CONFIRM_THRESHOLD = 20;
 
@@ -119,6 +128,25 @@ export class QueuePanel
     @property({ type: Boolean, reflect: true })
     overlay = false;
 
+    /**
+     * Phone width, from `matchMedia` rather than from a media query,
+     * because it decides whether the scrim *exists* (#171) —
+     * `job-band`'s rule, and a stylesheet cannot express it: a
+     * `display: none` scrim is still an element with a click handler.
+     *
+     * Below 600px the panel spans the whole content area, so the scrim
+     * has no uncovered pixels: measured at 424x439, host, panel and
+     * scrim are all 424x318 with the scrim entirely underneath. It dims
+     * nothing and dismisses nothing there, and the queue is a *screen*
+     * at that width anyway (#55) — back and a 44px close button are its
+     * ways out. Between 600 and 899 the panel is a 320px column of a
+     * wider content area, the scrim is reachable, and #24's
+     * tap-outside-to-close is real; that band is untouched.
+     */
+    @state() private phone = false;
+
+    private phoneQuery?: MediaQueryList;
+
     @state()
     private isDragging = false;
 
@@ -140,13 +168,13 @@ export class QueuePanel
     private delegationAttached = false;
 
     @query('#add-to-playlist-popup')
-    private addToPlaylistPopup!: WaPopup;
+    private addToPlaylistPopup!: MenuSurface;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     /** Unsubscribes the credit-arrival repaint. */
     private creditsUnsub?: () => void;
@@ -305,11 +333,11 @@ export class QueuePanel
     // ContextMenuHost interface
     // =================================================================
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -390,6 +418,8 @@ export class QueuePanel
             display: none;
         }
 
+        /* Overlay only, and above 600px only -- see the phone field,
+           which is where that half is decided (#171). */
         .scrim {
             position: absolute;
             inset: 0;
@@ -413,10 +443,10 @@ export class QueuePanel
 
             /* A screen's way out has to be hittable with a thumb.
                Measured at 424x439 before #55: these were **25x21px**,
-               and with the panel spanning the whole width the scrim
+               and with the panel spanning the whole width there is no
-               underneath has no uncovered pixels at all -- so it was
+               scrim here at all (#171) -- so this is the only pointer
-               the only pointer route out of a full-screen surface.
+               route out of a full-screen surface. Back answers it now
-               Back answers it now as well, which is the other half.
+               as well, which is the other half.
 
                Sized only in overlay mode: inline these sit in a 320px
                column beside the content, where a mouse is what reaches
@@ -551,8 +581,14 @@ export class QueuePanel
             contain: strict;
         }
 
-        .track-item:hover {
+        /* A hover tint is for a device that hovers (#54). A hold
-            background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+           synthesises a hover in the WebView, so ungated this arrives
+           because a finger touched the row and stays after it has
+           gone; the press state below is what a tap gets instead. */
+        @media (hover: hover) and (pointer: fine) {
+            .track-item:hover {
+                background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+            }
         }
 
         .track-item.selected {
@@ -567,6 +603,19 @@ export class QueuePanel
             background-color: var(--yj-selection-bg, rgba(100, 160, 255, 0.15));
         }
 
+        /* The press state (#54): the feedback a tap has now that the
+           web view's own highlight box is gone (index.css). Last, and
+           carrying a class, because a selected or playing row is two
+           classes deep and a bare :active would lose to it. */
+        .track-item.selected:active,
+        .track-item.active:active,
+        .track-item:active {
+            background-color: var(
+                --yj-press-overlay,
+                rgba(255, 255, 255, 0.12)
+            );
+        }
+
         .track-position {
             font-size: var(--yj-text-sm);
             color: var(--yj-text-tertiary, #888);
@@ -638,23 +687,42 @@ export class QueuePanel
             text-overflow: ellipsis;
         }
 
+        /*
+         * The per-row remove is a hover affordance, and on a device
+         * without hover it is redundant rather than missing: the row's
+         * context menu is a bottom sheet since #60 and carries "Remove
+         * from Queue", so the action is one long-press away. An
+         * always-visible X would instead spend part of a 424px row on
+         * something already reachable. #68's treatment, for #68's reason.
+         *
+         * display:none outside the query rather than visibility:hidden:
+         * a hidden button still occupies its hit area and is still in
+         * the accessibility tree, so a phone would keep a target for a
+         * control it can never see.
+         */
         .remove-button {
-            background: none;
+            display: none;
-            border: none;
-            color: var(--yj-text-tertiary, #888);
-            cursor: pointer;
-            padding: 4px;
-            display: flex;
-            align-items: center;
-            visibility: hidden;
         }
 
-        .track-item:hover .remove-button {
+        @media (hover: hover) and (pointer: fine) {
-            visibility: visible;
+            .remove-button {
-        }
+                background: none;
+                border: none;
+                color: var(--yj-text-tertiary, #888);
+                cursor: pointer;
+                padding: 4px;
+                display: flex;
+                align-items: center;
+                visibility: hidden;
+            }
 
-        .remove-button:hover {
+            .track-item:hover .remove-button {
-            color: var(--yj-error-text, #ff8787);
+                visibility: visible;
+            }
+
+            .remove-button:hover {
+                color: var(--yj-error-text, #ff8787);
+            }
         }
 
         .list-area.drag-over {
@@ -802,6 +870,8 @@ export class QueuePanel
         virtEl.addEventListener('dragstart', this.onDelegatedDragStart);
         virtEl.addEventListener('dragend', this.onTrackDragEnd);
         virtEl.addEventListener('keydown', this.onDelegatedKeydown);
+        virtEl.addEventListener('yj-tap', this.onRowTap);
+        virtEl.addEventListener('yj-long-press', this.onRowLongPress);
         this.delegationAttached = true;
     }
 
@@ -827,6 +897,12 @@ export class QueuePanel
         // desktop width rather than the minimum.
         this.updateOverlayMode();
 
+        // Read here rather than in a field initialiser, so a test can
+        // install its own matchMedia before the element is created.
+        this.phoneQuery = window.matchMedia?.(PHONE_QUERY);
+        this.phone = this.phoneQuery?.matches ?? false;
+        this.phoneQuery?.addEventListener('change', this.onPhoneMedia);
+
         if (this.parentElement) {
             this.spaceObserver = new ResizeObserver(() =>
                 this.updateOverlayMode(),
@@ -869,6 +945,8 @@ export class QueuePanel
         this.creditsUnsub = undefined;
         this.spaceObserver?.disconnect();
         this.spaceObserver = undefined;
+        this.phoneQuery?.removeEventListener('change', this.onPhoneMedia);
+        this.phoneQuery = undefined;
         document.removeEventListener('keydown', this.onOverlayKeydown);
         document.removeEventListener(
             'mousemove',
@@ -912,6 +990,8 @@ export class QueuePanel
             virtEl.removeEventListener('dragstart', this.onDelegatedDragStart);
             virtEl.removeEventListener('dragend', this.onTrackDragEnd);
             virtEl.removeEventListener('keydown', this.onDelegatedKeydown);
+            virtEl.removeEventListener('yj-tap', this.onRowTap);
+            virtEl.removeEventListener('yj-long-press', this.onRowLongPress);
         }
         this.delegationAttached = false;
     }
@@ -935,6 +1015,10 @@ export class QueuePanel
         this.overlay = available - this.panelWidth < MAIN_PANEL_FLOOR;
     };
 
+    private onPhoneMedia = (e: MediaQueryListEvent): void => {
+        this.phone = e.matches;
+    };
+
     /**
      * Escape closes a scrimmed overlay, which is the one keyboard rule
      * every dialog in this app already follows.
@@ -1092,7 +1176,7 @@ export class QueuePanel
         }
     }
 
-    private closePlaylistPicker() {
+    private closePlaylistPicker = () => {
         if (!this.playlistPickerOpen) return;
 
         this.playlistPickerOpen = false;
@@ -1102,7 +1186,7 @@ export class QueuePanel
         if (popup) {
             popup.active = false;
         }
-    }
+    };
 
     private onPlaylistActionComplete = () => {
         this.closePlaylistPicker();
@@ -1193,6 +1277,92 @@ export class QueuePanel
         this.queue.playAtIndex(index);
     }
 
+    // =================================================================
+    // A finger on a queue row (plan 019 phase 3, #63)
+    // =================================================================
+
+    /**
+     * A tap plays this position in the queue.
+     *
+     * `track-list`'s tap sets the queue to the list it was made in;
+     * copying that here would rebuild the queue from the queue, which
+     * is not the no-op it looks like -- it would discard the queue's
+     * source, its shuffle order and everything a user had inserted by
+     * hand. `playAtIndex` is what a double-click already does, and it
+     * is what a tap means.
+     */
+    private onRowTap = (e: GestureEvent) => {
+        const idx = this.resolveTrackIndexFromEvent(e);
+
+        if (idx === null) return;
+
+        // A control inside the row owns its own tap -- the same rule
+        // the shortcut service has for a focused control that owns a
+        // key. The remove button is the one here.
+        if ((e.target as HTMLElement).closest('.remove-button')) return;
+
+        e.preventDefault();
+
+        // The roving tab stop follows the finger, or Tab returns to
+        // wherever the arrows last were rather than to the row that was
+        // just touched.
+        this.focusedIndex = idx;
+
+        if (this.selection.selectionMode) {
+            this.selection.toggleInMode(String(idx), idx);
+            this.virtualizer?.requestUpdate();
+
+            return;
+        }
+
+        this.selection.clear();
+        this.queue.playAtIndex(idx);
+    };
+
+    private onRowLongPress = (e: GestureEvent) => {
+        const idx = this.resolveTrackIndexFromEvent(e);
+
+        if (idx === null) return;
+
+        e.preventDefault();
+        this.focusedIndex = idx;
+        this.selection.enterSelectionMode(String(idx), idx);
+        this.virtualizer?.requestUpdate();
+    };
+
+    /**
+     * The two worth a thumb, and "More" for the rest.
+     *
+     * Remove is here rather than left to the overflow because it is
+     * what a selection in a *queue* is most often made for, and it is
+     * the action the row's own × offers one row at a time.
+     */
+    private static readonly SELECTION_ACTIONS: SelectionAction[] = [
+        { id: 'play', label: 'Play', icon: ICON_PLAY },
+        { id: 'remove', label: 'Remove', icon: ICON_REMOVE, danger: true },
+    ];
+
+    private renderSelectionBar() {
+        if (!this.selection.selectionMode) return nothing;
+
+        return html`
+            <selection-bar
+                .count=${this.selection.selectionCount}
+                .actions=${QueuePanel.SELECTION_ACTIONS}
+                @selection-exit=${this.onSelectionExit}
+                @selection-action=${(e: CustomEvent<{ id: string }>) =>
+                this.onContextMenuAction(e.detail.id)}
+                @selection-more=${(e: CustomEvent<{ x: number; y: number }>) =>
+                this.ctxMenu.openAt(e.detail.x, e.detail.y)}
+            ></selection-bar>
+        `;
+    }
+
+    private onSelectionExit = () => {
+        this.selection.exitSelectionMode();
+        this.virtualizer?.requestUpdate();
+    };
+
     private handleTrackContextMenu(
         e: MouseEvent,
         index: number,
@@ -1475,6 +1645,29 @@ export class QueuePanel
             .map((i) => tracks[i]!.filePath);
     }
 
+    /**
+     * The row "Go to Artist" / "Go to Album" navigate from, which is
+     * one row or none — the rule the Play item already follows.  Both
+     * items are drawn only below the phone breakpoint, where the row's
+     * own names stopped being links (#67).
+     */
+    private get goToTarget(): GoToTarget | undefined {
+        const indices = this.selection.getSelectedIndices();
+
+        if (indices.length !== 1) return undefined;
+
+        const track = this.queue.tracks[indices[0]!];
+
+        if (!track) return undefined;
+
+        return {
+            artistName: track.artist,
+            artistMBID: track.artistMbid,
+            albumName: track.album,
+            albumMBID: track.releaseGroupMbid,
+        };
+    }
+
     // =================================================================
     // Drop target (tracks dropped into queue)
     // =================================================================
@@ -1971,7 +2164,7 @@ export class QueuePanel
         const tracks = this.queue.tracks;
 
         return html`
-            ${this.overlay
+            ${this.overlay && !this.phone
                 ? html`<div
                       class="scrim"
                       part="scrim"
@@ -2042,9 +2235,11 @@ export class QueuePanel
                     </div>
                 </div>
 
-                <wa-popup
+                <menu-surface
                     id="add-to-playlist-popup"
+                    label="Add to playlist"
                     placement="bottom-end"
+                    @menu-dismiss=${this.closePlaylistPicker}
                     .active=${this.playlistPickerOpen}
                 >
                     ${this.playlistPickerOpen
@@ -2060,7 +2255,7 @@ export class QueuePanel
                               ></playlist-picker>
                           `
                         : nothing}
-                </wa-popup>
+                </menu-surface>
 
                 <div
                     class="list-area"
@@ -2101,13 +2296,11 @@ export class QueuePanel
                               ></lit-virtualizer>
                           `}
                 </div>
+                ${this.renderSelectionBar()}
             </div>
 
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu.contextMenuOpen}
             >
                 ${this.ctxMenu.contextMenuOpen
@@ -2192,16 +2385,23 @@ export class QueuePanel
                                   Track
                                   Details
                               </wa-dropdown-item>
+                              ${goToMenuItems(this.goToTarget, {
+                                  onSelect: () => {
+                                      this.selection.clear();
+                                      this.ctxMenu.close();
+                                  },
+                                  onHover: () =>
+                                      this.ctxMenu.closePlaylistSubmenu(),
+                              })}
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu.playlistSubmenuOpen}
             >
                 ${this.ctxMenu.playlistSubmenuOpen &&
@@ -2224,7 +2424,7 @@ export class QueuePanel
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
             <track-details></track-details>
         `;

frontend/src/components/search-dialog/search-trigger.ts

@@ -61,11 +61,32 @@ export class SearchTrigger extends LitElement {
                 display: inline-flex;
                 align-items: center;
                 justify-content: center;
-                /* The smallest a touch target should be. The header's
+                /* The app's touch floor, from #56 -- and this is the
-                   own action buttons are smaller because they carry a
+                   control that should least have to argue for it: #57
-                   label; this one is a glyph. */
+                   created it as the phone's replacement for the header
-                min-width: 40px;
+                   search box, so it exists *only* where there is a
-                min-height: 40px;
+                   thumb.
+
+                   It shipped at 40px under a comment calling that "the
+                   smallest a touch target should be", which was the
+                   floor being restated four pixels short rather than a
+                   second opinion about it (#186). The rest of that
+                   comment said the header's own action buttons are
+                   smaller because they carry a label; they are 44px
+                   now too, so that no longer distinguishes anything.
+
+                   The extra width is a target rather than a box, for
+                   page-header's reason: this button sits in that
+                   header, whose overflow fit (#69) measures inline
+                   size, and four pixels there is four pixels the
+                   trigger for every collapsed action does not get at
+                   320px. Height is free -- nothing measures it. */
+                min-width: 44px;
+                min-height: 44px;
+                /* Border-box, so the 44 above is the whole target and
+                   the margin is what hands the four extra pixels back
+                   to the row. */
+                margin-inline: -2px;
                 padding: 0;
                 background: none;
                 border: 1px solid var(--yj-border-subtle, #555);

frontend/src/components/selection-bar/selection-bar.ts

@@ -0,0 +1,218 @@
+import { LitElement, html, css, nothing } from 'lit';
+import { customElement, property } from 'lit/decorators.js';
+import '@awesome.me/webawesome/dist/components/icon/icon.js';
+import { designTokens } from '../../styles/tokens.css';
+import { ICON_MORE_ACTIONS } from '@utils/icon-language';
+
+/**
+ * What a selection can have done to it, while a finger is holding one.
+ *
+ * This is the context menu (plan 019, #63). Not a second surface
+ * beside it — the same actions, contextualised to whatever is
+ * selected, in the shape Android puts them in.
+ *
+ * #63 asked for a double tap to open the menu instead. That mapping
+ * costs the app's primary interaction 250ms on every play, because the
+ * first tap of a double tap is indistinguishable from a single tap
+ * until the interval expires, and playing a track is ~100ms end to end
+ * on the reference device. So there is no double tap: a long press
+ * selects, this says what can be done, and the sheet behind "More" is
+ * the same `menu-surface` every other menu in the app opens.
+ *
+ * Four things about it are load-bearing.
+ *
+ * **It is presentational.** It takes a count and a list of actions and
+ * emits `selection-action` / `selection-exit`; it holds no selection
+ * and calls no store. The host already owns a `SelectionController`
+ * and an action handler, and a bar that reached for either would be a
+ * second definition of what "play the selection" means — the fault
+ * `utils/library-status.ts` exists to have fixed one feature over.
+ *
+ * **The bar is only what fits, and "More" is the rest.** A context
+ * menu can be nine items because it is a sheet; a bar is one row on a
+ * 424px screen. So the host passes the two or three worth a thumb and
+ * the overflow opens the menu it already renders, which is what keeps
+ * every action reachable at every size — plan 018's promise, and the
+ * reason this cannot simply drop the long tail.
+ *
+ * **Its controls are 44px** (#56, #186), and the count is a live
+ * region: the number changes under the user's finger as they tap rows,
+ * and nothing else on screen announces it.
+ *
+ * **Escape leaves the mode, from here rather than from each host.**
+ * This element exists only while the mode does, so it is the one place
+ * a dismissal can be attached and detached with the thing it
+ * dismisses. It is the same exception the overlaid queue's Escape is.
+ *
+ * **It renders nothing at zero.** The mode ends when the last row is
+ * deselected — `SelectionController.toggleInMode` is where that is
+ * decided — so a bar with a count of none is a state this should never
+ * be asked to draw, and drawing it anyway would hide the fact that it
+ * has been.
+ */
+export interface SelectionAction {
+    id: string;
+    label: string;
+    icon: string;
+    danger?: boolean;
+}
+
+@customElement('selection-bar')
+export class SelectionBar extends LitElement {
+    static override styles = [
+        designTokens,
+        css`
+            :host {
+                display: block;
+            }
+
+            .bar {
+                display: flex;
+                align-items: center;
+                gap: 0.25em;
+                padding: 0.25em 0.5em;
+                background: var(--yj-bg-elevated, #343a40);
+                border-top: 1px solid var(--yj-border-subtle, #333);
+            }
+
+            .count {
+                flex: 1;
+                min-width: 0;
+                font-size: var(--yj-text-md);
+                font-weight: 600;
+                color: var(--yj-text-primary, #fff);
+                white-space: nowrap;
+                overflow: hidden;
+                text-overflow: ellipsis;
+            }
+
+            /* 44px, from #56 and #186 -- this is a bar a thumb uses. */
+            button {
+                display: flex;
+                align-items: center;
+                justify-content: center;
+                min-inline-size: 44px;
+                min-block-size: 44px;
+                padding: 0 0.5em;
+                border: none;
+                border-radius: 4px;
+                background: none;
+                color: var(--yj-text-primary, #fff);
+                font-family: inherit;
+                font-size: var(--yj-text-md);
+                cursor: pointer;
+            }
+
+            button:hover {
+                background: var(--yj-bg-overlay, #495057);
+            }
+
+            button.danger {
+                color: var(--yj-error-text, #ff8787);
+            }
+        `,
+    ];
+
+    /** How many items are selected. Zero renders nothing. */
+    @property({ type: Number }) count = 0;
+
+    /** The actions worth a thumb. The rest live behind "More". */
+    @property({ attribute: false }) actions: SelectionAction[] = [];
+
+    private emit(name: string, detail?: unknown) {
+        this.dispatchEvent(
+            new CustomEvent(name, { detail, bubbles: true, composed: true }),
+        );
+    }
+
+    /**
+     * Escape leaves the mode.
+     *
+     * A mode changes what a tap means, so it has to have an exit that
+     * is not "find the ×" -- and this is the documented exception to
+     * the app's one-keyboard-authority rule, on exactly the grounds
+     * the overlaid queue's Escape is: **it is a dismissal, not a
+     * shortcut**, so it is not a panel-scoped binding and it is
+     * attached only while there is something to dismiss. Putting it
+     * here rather than in each host is what gives all four surfaces
+     * the same answer, since this element exists only while the mode
+     * does.
+     *
+     * The platform's own back gesture is the other half of that and is
+     * deliberately *not* here: the shell owns the history stack
+     * (#6/#55), and a component reaching for `history` itself is how
+     * two stacks come to disagree about what one press means -- the
+     * fault that deleted `navStack`. See #200.
+     */
+    private onKeydown = (e: KeyboardEvent) => {
+        if (e.key !== 'Escape' || this.count <= 0) return;
+
+        e.preventDefault();
+        e.stopPropagation();
+        this.emit('selection-exit');
+    };
+
+    override connectedCallback() {
+        super.connectedCallback();
+        document.addEventListener('keydown', this.onKeydown, true);
+    }
+
+    override disconnectedCallback() {
+        super.disconnectedCallback();
+        document.removeEventListener('keydown', this.onKeydown, true);
+    }
+
+    override render() {
+        if (this.count <= 0) return nothing;
+
+        const noun = this.count === 1 ? 'track' : 'tracks';
+
+        return html`
+            <div class="bar" role="toolbar" aria-label="Selection actions">
+                <button
+                    aria-label="Leave selection"
+                    @click=${() => this.emit('selection-exit')}
+                >
+                    <wa-icon name="xmark"></wa-icon>
+                </button>
+                <span class="count" role="status" aria-live="polite">
+                    ${this.count.toLocaleString()} ${noun} selected
+                </span>
+                ${this.actions.map(
+                    (action) => html`
+                        <button
+                            class=${action.danger ? 'danger' : ''}
+                            aria-label=${action.label}
+                            title=${action.label}
+                            @click=${() =>
+                                this.emit('selection-action', { id: action.id })}
+                        >
+                            <wa-icon name=${action.icon}></wa-icon>
+                        </button>
+                    `,
+                )}
+                <button
+                    aria-label="More actions"
+                    @click=${(e: MouseEvent) => {
+                        const box = (
+                            e.currentTarget as HTMLElement
+                        ).getBoundingClientRect();
+
+                        this.emit('selection-more', {
+                            x: box.left,
+                            y: box.top,
+                        });
+                    }}
+                >
+                    <wa-icon name=${ICON_MORE_ACTIONS}></wa-icon>
+                </button>
+            </div>
+        `;
+    }
+}
+
+declare global {
+    interface HTMLElementTagNameMap {
+        'selection-bar': SelectionBar;
+    }
+}

frontend/src/components/sidebar/app-sidebar.ts

@@ -42,6 +42,26 @@ export class AppSidebar extends LitElement {
             scrollbar-width: thin;
         }
 
+        /* A host that has made room owns the box, not just the labels
+           (#71). The bottom-nav sheet is the width of the screen and
+           provides the one scroll container it needs; left to itself
+           the sidebar is a 200px column with a second scroller inside
+           it, which is what a nested scroll region feels like under a
+           thumb -- part of the surface moves and part of it does not. */
+        :host([expanded]) {
+            max-width: none;
+            height: auto;
+            overflow: visible;
+        }
+
+        /* And the width is not draggable there. It is a mouse
+           affordance (mousedown, col-resize) sitting on the right edge
+           of a touch surface, where the compatibility mouse events a
+           tap synthesises can start a resize nobody asked for. */
+        :host([expanded]) .resize-handle {
+            display: none;
+        }
+
         .resize-handle {
             position: absolute;
             top: 0;
@@ -95,8 +115,15 @@ export class AppSidebar extends LitElement {
             text-align: center;
         }
 
-        li button:hover {
+        /* A hover tint is for a device that hovers (#54), and this
-            background-color: var(--yj-bg-elevated, #343a40);
+           component is on a phone too: below 600px it is what
+           bottom-nav's "More" sheet mounts, where a hold
+           synthesises a hover and leaves a destination looking picked
+           after the finger has gone. */
+        @media (hover: hover) and (pointer: fine) {
+            li button:hover {
+                background-color: var(--yj-bg-elevated, #343a40);
+            }
         }
 
         li button:focus-visible {
@@ -108,6 +135,14 @@ export class AppSidebar extends LitElement {
             background-color: var(--yj-bg-overlay, #495057);
         }
 
+        /* The press state (#54), after the .active rule and at the same
+           specificity, so pressing the destination you are already on
+           still says something. It is what a tap gets now that
+           index.css has taken the web view's own highlight box away. */
+        li button:active {
+            background-color: var(--yj-press-overlay, rgba(255, 255, 255, 0.12));
+        }
+
         li button p {
             margin: 0;
             white-space: nowrap;
@@ -145,6 +180,25 @@ export class AppSidebar extends LitElement {
         :host(.collapsed) li button wa-icon {
             font-size: var(--yj-icon-md);
         }
+
+        /* Below 600px the only place this renders is the bottom-nav
+           sheet -- the shell's own copy is display: none there -- so
+           the rows are sized for the thumb that opened it: 48px, which
+           is #186's floor and the height every row in #60's context
+           sheet already has. A media query inside a shadow root is
+           answered by the viewport, so the component states this
+           itself rather than the sheet reaching in. */
+        @media (max-width: 599px) {
+            ul {
+                padding: 4px 8px 8px;
+            }
+
+            li button {
+                min-height: 48px;
+                padding: 12px 10px;
+                gap: 14px;
+            }
+        }
     `];
 
     /** Delay in ms before a drag-hover triggers navigation. */
@@ -173,11 +227,14 @@ export class AppSidebar extends LitElement {
 
     /**
      * Keep the labels regardless of the viewport, for a host that has
-     * made room for them -- `bottom-nav`'s drawer, which is the whole
+     * made room for them -- `bottom-nav`'s sheet, which is the whole
      * screen wide on the phone where this would otherwise auto-collapse
      * to icons. The auto-collapse is a *width* response to a narrow
-     * shell, and inside a drawer the shell is not what the sidebar is
+     * shell, and inside a sheet the shell is not what the sidebar is
      * sharing space with.
+     *
+     * It says the host owns the *box*, not only the labels: the width,
+     * the scrolling and the resize handle all follow it (#71).
      */
     @property({ type: Boolean, reflect: true })
     expanded = false;
@@ -350,9 +407,18 @@ export class AppSidebar extends LitElement {
      * be a media query in the stylesheet.
      */
     private applyViewportWidth() {
-        const narrow =
+        // A host that made room decides how much: `bottom-nav`'s sheet
-            !this.expanded &&
+        // is the whole screen wide, and the inline width below -- which
-            (this.narrowViewport?.matches ?? false);
+        // beats any rule the host could write -- would draw the old
+        // 200px side drawer inside it.
+        if (this.expanded) {
+            this.style.width = '100%';
+            this.collapsed = false;
+
+            return;
+        }
+
+        const narrow = this.narrowViewport?.matches ?? false;
         const width = narrow
             ? MIN_WIDTH
             : this.userWidth;

frontend/src/components/smart-playlist-details/smart-playlist-details.ts

@@ -26,8 +26,12 @@ import {
     contextMenuStyles,
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { focusRovingRow, nextRovingIndex } from '@utils/roving-rows';
+import type { GestureEvent } from '@utils/touch-gestures';
+import { SwipeToQueue, swipeRevealStyles } from '@utils/swipe-to-queue';
+import '@components/selection-bar/selection-bar';
+import type { SelectionAction } from '@components/selection-bar/selection-bar';
 import { FavoritesController } from '@store/controllers/favorites-controller';
 import {
     setDragPayload,
@@ -40,7 +44,8 @@ import {
 } from '@utils/drag-image';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@lit-labs/virtualizer';
 import type { LitVirtualizer } from '@lit-labs/virtualizer';
@@ -59,10 +64,16 @@ import {
     trackLink,
     exploreLinkStyles,
 } from '@utils/explore-link';
+import { goToMenuItems } from '@utils/go-to-menu';
+import type { GoToTarget } from '@utils/go-to-menu';
 import '@components/smart-playlist-editor/smart-playlist-editor.js';
 import { designTokens } from '../../styles/tokens.css';
+import { backButton } from '../../styles/back-button.css';
+import { srOnly } from '../../styles/sr-only.css';
 import { list } from '@utils/binding';
 import {
+    ICON_PLAY,
+    ICON_PLAY_NEXT,
     ICON_PLAYLIST,
     ICON_QUEUE,
     ICON_SMART_PLAYLIST,
@@ -176,10 +187,10 @@ export class SmartPlaylistDetails
     private dragImageEl: HTMLElement | null = null;
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     @query('track-details')
     private trackDetailsDialog!: TrackDetails;
@@ -188,11 +199,11 @@ export class SmartPlaylistDetails
     // ContextMenuHost interface
     // =================================================================
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -241,8 +252,11 @@ export class SmartPlaylistDetails
 
     static override styles = [
         designTokens,
+        srOnly,
+        backButton,
         contextMenuStyles,
         exploreLinkStyles,
+        swipeRevealStyles,
         css`
         :host {
             display: flex;
@@ -268,31 +282,6 @@ export class SmartPlaylistDetails
                 );
         }
 
-        .back-button {
-            display: flex;
-            align-items: center;
-            justify-content: center;
-            width: 32px;
-            height: 32px;
-            border: none;
-            border-radius: 50%;
-            background: var(
-                --yj-bg-overlay,
-                rgba(255, 255, 255, 0.06)
-            );
-            color: var(--yj-text-primary, #fff);
-            cursor: pointer;
-            flex-shrink: 0;
-            transition: background-color 0.15s ease;
-        }
-
-        .back-button:hover {
-            background: var(
-                --yj-bg-hover,
-                rgba(255, 255, 255, 0.12)
-            );
-        }
-
         .back-button wa-icon {
             font-size: 16px;
         }
@@ -466,6 +455,9 @@ export class SmartPlaylistDetails
         .track-item {
             width: 100%;
             box-sizing: border-box;
+            /* The swipe reveal is absolute inside the row. */
+            position: relative;
+            overflow: hidden;
         }
 
         .track-header {
@@ -524,8 +516,14 @@ export class SmartPlaylistDetails
             user-select: none;
         }
 
-        .track-item:hover {
+        /* A hover tint is for a device that hovers (#54). A hold
-            background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+           synthesises a hover in the WebView, so ungated this arrives
+           because a finger touched the row and stays after it has
+           gone; the press state below is what a tap gets instead. */
+        @media (hover: hover) and (pointer: fine) {
+            .track-item:hover {
+                background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+            }
         }
 
         .track-item.selected {
@@ -541,6 +539,19 @@ export class SmartPlaylistDetails
             background-color: var(--yj-selection-bg, rgba(100, 160, 255, 0.15));
         }
 
+        /* The press state (#54): the feedback a tap has now that the
+           web view's own highlight box is gone (index.css). Last, and
+           carrying a class, because a selected or playing row is two
+           classes deep and a bare :active would lose to it. */
+        .track-item.selected:active,
+        .track-item.active:active,
+        .track-item:active {
+            background-color: var(
+                --yj-press-overlay,
+                rgba(255, 255, 255, 0.12)
+            );
+        }
+
         /* Phantom rows span the full grid */
         .track-item.phantom {
             display: grid;
@@ -938,10 +949,136 @@ export class SmartPlaylistDetails
             .map((i) => this.tracks[i]!.FilePath);
     }
 
+    /**
+     * The row "Go to Artist" / "Go to Album" navigate from — one row
+     * or none, and only below the phone breakpoint, where the row's
+     * own names stopped being links (#67).
+     */
+    private get goToTarget(): GoToTarget | undefined {
+        const indices = this.selection.getSelectedIndices();
+
+        if (indices.length !== 1) return undefined;
+
+        const track = this.tracks[indices[0]!];
+
+        if (!track) return undefined;
+
+        return {
+            artistName: track.Artist,
+            artistMBID: track.ArtistMBID,
+            albumName: track.Album,
+            albumMBID: track.ReleaseGroupMBID,
+        };
+    }
+
     // =================================================================
     // Context menu actions
     // =================================================================
 
+    // =================================================================
+    // A finger on a smart playlist row (plan 019 phase 3, #63)
+    // =================================================================
+
+    /** The row an announced gesture is on, with its track. */
+    private rowFromGesture(
+        e: Event,
+    ): { index: number; track: playlist.Track } | null {
+        const row = (e.target as HTMLElement).closest(
+            '.track-item',
+        ) as HTMLElement | null;
+
+        if (!row) return null;
+
+        const index = Number(row.dataset.index);
+        const track = this.tracks[index];
+
+        if (Number.isNaN(index) || !track) return null;
+
+        return { index, track };
+    }
+
+    /** A tap plays the playlist from that row -- `playlist-details`'
+     *  rule, and the app's: activating a row plays the list it is in. */
+    private onRowTap = (e: GestureEvent) => {
+        const hit = this.rowFromGesture(e);
+
+        if (!hit) return;
+
+        if (this.selection.selectionMode) {
+            e.preventDefault();
+            this.focusedIndex = hit.index;
+            this.selection.toggleInMode(String(hit.index), hit.index);
+            this.virtualizer?.requestUpdate();
+
+            return;
+        }
+
+        // A missing file has nothing to play, so the tap falls through
+        // to the click that selects it.
+        if (hit.track.Phantom) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+        this.handleTrackDblClick(hit.index);
+    };
+
+    private onRowLongPress = (e: GestureEvent) => {
+        const hit = this.rowFromGesture(e);
+
+        if (!hit) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+        this.selection.enterSelectionMode(String(hit.index), hit.index);
+        this.virtualizer?.requestUpdate();
+    };
+
+    private swipe = new SwipeToQueue(this, {
+        resolve: (e) => {
+            const hit = this.rowFromGesture(e);
+
+            if (!hit || hit.track.Phantom) return null;
+
+            const selected = this.selection.getSelectedIndices();
+            const many =
+                selected.length > 1 && selected.includes(hit.index);
+            const filePaths = many
+                ? this.getSelectedFilePaths()
+                : [hit.track.FilePath];
+
+            return { index: hit.index, filePaths, label: hit.track.Title };
+        },
+        repaint: () => this.virtualizer?.requestUpdate(),
+    });
+
+    /** The three worth a thumb; the sheet behind "More" is the rest. */
+    private static readonly SELECTION_ACTIONS: SelectionAction[] = [
+        { id: 'play', label: 'Play', icon: ICON_PLAY },
+        { id: 'add-to-queue', label: 'Add to queue', icon: ICON_QUEUE },
+        { id: 'play-next', label: 'Play next', icon: ICON_PLAY_NEXT },
+    ];
+
+    private renderSelectionBar() {
+        if (!this.selection.selectionMode) return nothing;
+
+        return html`
+            <selection-bar
+                .count=${this.selection.selectionCount}
+                .actions=${SmartPlaylistDetails.SELECTION_ACTIONS}
+                @selection-exit=${this.onSelectionExit}
+                @selection-action=${(e: CustomEvent<{ id: string }>) =>
+                this.onContextMenuAction(e.detail.id)}
+                @selection-more=${(e: CustomEvent<{ x: number; y: number }>) =>
+                this.ctxMenu.openAt(e.detail.x, e.detail.y)}
+            ></selection-bar>
+        `;
+    }
+
+    private onSelectionExit = () => {
+        this.selection.exitSelectionMode();
+        this.virtualizer?.requestUpdate();
+    };
+
     private onContextMenuAction(action: string) {
         const filePaths = this.getSelectedFilePaths();
 
@@ -1356,6 +1493,9 @@ export class SmartPlaylistDetails
                 <div class="header-cell col-album">Album</div>
                 <div class="header-cell col-duration">Duration</div>
             </div>
+            <div class="sr-only" role="status" aria-live="polite">
+                ${this.swipe.announcement}
+            </div>
             <lit-virtualizer
                 role="listbox"
                 aria-label="Smart playlist tracks"
@@ -1364,7 +1504,13 @@ export class SmartPlaylistDetails
                 .renderItem=${this.renderRow}
                 .keyFunction=${this.rowKey}
                 .layout=${this.flowLayout}
+                @yj-tap=${this.onRowTap}
+                @yj-long-press=${this.onRowLongPress}
+                @yj-swipe-start=${this.swipe.onSwipeStart}
+                @yj-swipe-move=${this.swipe.onSwipeMove}
+                @yj-swipe-end=${this.swipe.onSwipeEnd}
             ></lit-virtualizer>
+            ${this.renderSelectionBar()}
         `;
     }
 
@@ -1386,6 +1532,7 @@ export class SmartPlaylistDetails
                         active ? 'active' : '',
                         selected ? 'selected' : '',
                         isPhantom ? 'phantom' : '',
+                        this.swipe.isSwiping(trackIndex) ? 'swiping' : '',
                     ]
                         .filter(Boolean)
                         .join(' ');
@@ -1396,6 +1543,7 @@ export class SmartPlaylistDetails
                             role="option"
                             aria-selected=${selected}
                             data-index=${trackIndex}
+                            data-swipe
                             tabindex=${trackIndex === this.focusedIndex ? 0 : -1}
                             @keydown=${(e: KeyboardEvent) =>
                                 this.onRowKeydown(e, trackIndex)}
@@ -1430,6 +1578,7 @@ export class SmartPlaylistDetails
                                 ? nothing
                                 : this.onTrackDragEnd}
                         >
+                            ${this.swipe.renderReveal(trackIndex)}
                             ${isPhantom
                                 ? html`<div class="phantom-row">
                                       <wa-icon
@@ -1465,11 +1614,8 @@ export class SmartPlaylistDetails
 
     private renderContextMenu() {
         return html`
-            <wa-popup
+            <menu-surface
                 id="context-menu"
-                placement="bottom-start"
-                flip
-                shift
                 .active=${this.ctxMenu.contextMenuOpen}
             >
                 ${this.ctxMenu.contextMenuOpen
@@ -1580,16 +1726,23 @@ export class SmartPlaylistDetails
                                   ></wa-icon>
                                   Track Details
                               </wa-dropdown-item>
+                              ${goToMenuItems(this.goToTarget, {
+                                  onSelect: () => {
+                                      this.selection.clear();
+                                      this.ctxMenu.close();
+                                  },
+                                  onHover: () =>
+                                      this.ctxMenu.closePlaylistSubmenu(),
+                              })}
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
 
-            <wa-popup
+            <menu-surface
                 id="playlist-submenu"
+                label="Add to playlist"
                 placement="right-start"
-                flip
-                shift
                 .active=${this.ctxMenu
                     .playlistSubmenuOpen}
             >
@@ -1616,7 +1769,7 @@ export class SmartPlaylistDetails
                           </div>
                       `
                     : nothing}
-            </wa-popup>
+            </menu-surface>
         `;
     }
 }

frontend/src/components/top-results-row/top-results-row.ts

@@ -371,8 +371,11 @@ export class TopResultsRow extends LitElement {
                         <span class="card-name">${r.name}</span>
                         ${artistPart || metaPart
                             ? html`<span class="card-subtitle"
-                                  >${artistPart
+                                  ><!-- keepOnPhone: this card has no
-                                      ? creditLink(creditStore.credits(r.mbid), artistPart, r.artistMbid ?? '')
+                                       context menu, so the credit is
+                                       the only route to the artist of
+                                       a top result (#67). -->${artistPart
+                                      ? creditLink(creditStore.credits(r.mbid), artistPart, r.artistMbid ?? '', { keepOnPhone: true })
                                       : nothing}${artistPart && metaPart
                                       ? ' · '
                                       : ''}${metaPart}</span

frontend/src/components/track-details/track-details.ts

@@ -529,6 +529,44 @@ export class TrackDetails extends LitElement {
             background: var(--yj-error, #e03131);
         }
 
+        /*
+         * Both are the *only* route to changing or removing a track's
+         * cover art, so where the device has no hover they are always
+         * visible rather than hidden — the inverse of #68's rule, which
+         * applies where the hover control is redundant. Revealed by
+         * opacity, so what is on screen is what the desktop reveal shows
+         * and nothing about the layout moves.
+         */
+        @media not all and (hover: hover) {
+            /* The × is genuinely the only route to removing the art, so
+               on a device that cannot hover it is simply always there.
+
+               The pen is not: .cover-art-edit carries the click that
+               opens the file picker, so tapping the artwork already
+               worked while the overlay was invisible. It is a discovery
+               hint — and paying for discovery by covering the artwork
+               being edited in 50% black, permanently, on every touch
+               device, is heavier than the hint is worth. It becomes a
+               corner chip in the remove button's own visual language
+               instead: same size, same disc, same alpha. */
+            .cover-art-remove {
+                opacity: 1;
+            }
+
+            .cover-art-overlay {
+                opacity: 1;
+                inset: auto 4px 4px auto;
+                width: 24px;
+                height: 24px;
+                border-radius: 50%;
+                background: rgba(0, 0, 0, 0.7);
+            }
+
+            .cover-art-overlay wa-icon {
+                font-size: 14px;
+            }
+        }
+
         /* Error message */
         .error-message {
             flex: 1;

frontend/src/components/track-list/track-list.ts

@@ -10,6 +10,10 @@ import {
 } from 'lit/decorators.js';
 import { SelectionController } from '@utils/selection-controller';
 import type { SelectionHost } from '@utils/selection-controller';
+import type { GestureEvent } from '@utils/touch-gestures';
+import { SwipeToQueue, swipeRevealStyles } from '@utils/swipe-to-queue';
+import '@components/selection-bar/selection-bar';
+import type { SelectionAction } from '@components/selection-bar/selection-bar';
 import { ViewLifecycleMixin } from '@utils/view-lifecycle';
 import { PHONE_QUERY } from '@utils/breakpoints';
 import {
@@ -18,7 +22,7 @@ import {
     isContextMenuKey,
 } from '@utils/context-menu-controller.js';
 
-import type { ContextMenuHost } from '@utils/context-menu-controller.js';
+import type { ContextMenuHost, MenuTarget } from '@utils/context-menu-controller.js';
 import { PlayerController } from '@store/controllers/player-controller';
 import { SearchController } from '@store/controllers/search-controller';
 import '@components/page-header/page-header';
@@ -47,6 +51,8 @@ import {
     trackLink,
     exploreLinkStyles,
 } from '@utils/explore-link';
+import { goToMenuItems } from '@utils/go-to-menu';
+import type { GoToTarget } from '@utils/go-to-menu';
 import {
     setDragPayload,
     emitDragActive,
@@ -63,7 +69,8 @@ import type {
 } from '@lit-labs/virtualizer';
 import { flow } from '@lit-labs/virtualizer/layouts/flow.js';
 import '@awesome.me/webawesome/dist/components/popup/popup.js';
-import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
+import type { MenuSurface } from '../menu-surface/menu-surface';
+import '../menu-surface/menu-surface';
 import '@awesome.me/webawesome/dist/components/dropdown-item/dropdown-item.js';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import { describeError } from '@utils/describe-error';
@@ -76,7 +83,9 @@ import '@components/playlist-picker/playlist-picker.js';
 import type { TrackDetails } from '@components/track-details/track-details.js';
 import type { CoverArtUrls } from '@components/track-details/track-details.js';
 import {
+    ICON_PLAY,
     ICON_PLAYLIST,
+    ICON_PLAY_NEXT,
     ICON_QUEUE,
 } from '@utils/icon-language';
 
@@ -231,18 +240,18 @@ export class TrackList
     private tracks: library.Track[] = [];
 
     @query('#context-menu')
-    private contextMenuPopup!: WaPopup;
+    private contextMenuPopup!: MenuSurface;
 
     @query('#playlist-submenu')
-    private playlistSubmenuPopup!: WaPopup;
+    private playlistSubmenuPopup!: MenuSurface;
 
     // -- ContextMenuHost interface --
 
-    getContextMenuPopup(): WaPopup | undefined {
+    getContextMenuPopup(): MenuTarget | undefined {
         return this.contextMenuPopup;
     }
 
-    getPlaylistSubmenuPopup(): WaPopup | undefined {
+    getPlaylistSubmenuPopup(): MenuTarget | undefined {
         return this.playlistSubmenuPopup;
     }
 
@@ -276,6 +285,29 @@ export class TrackList
      *  path into it at all (H-5). */
     @state() private focusedIndex = 0;
 
+    /**
+     * Swipe a row right to queue it (plan 019 phase 2, #63).
+     *
+     * The affordance and the arithmetic are `utils/swipe-to-queue.ts`,
+     * shared with both playlist detail views; what stays here is what
+     * only this list knows -- which row an event is on, and what a
+     * swipe on it means when other rows are selected.
+     */
+    private swipe = new SwipeToQueue(this, {
+        resolve: (e) => {
+            const hit = this.resolveTrackFromEvent(e);
+
+            if (!hit) return null;
+
+            return {
+                index: hit.index,
+                filePaths: this.swipeTargetKeys(hit.track.FilePath),
+                label: hit.track.TrackName,
+            };
+        },
+        repaint: () => this.virtualizer?.requestUpdate(),
+    });
+
     private handleSelectAll = (): void => {
         this.selection.selectAll();
     };
@@ -1010,7 +1042,7 @@ export class TrackList
         this.requestUpdate();
     };
 
-    static override styles = [designTokens, srOnly, contextMenuStyles, exploreLinkStyles, css`
+    static override styles = [designTokens, srOnly, contextMenuStyles, exploreLinkStyles, swipeRevealStyles, css`
     :host {
       display: flex;
       flex-direction: column;
@@ -1169,8 +1201,16 @@ export class TrackList
       padding-left: 6px;
     }
 
-    .track-row:hover {
+    /* A hover tint is for a device that hovers (#54): a hold
-      background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+       synthesises a hover in the WebView, so ungated this is a
+       highlight that arrives because a finger touched the row and
+       then stays there after it has gone -- which reads as a
+       selection the user did not make. Same gate, and the same
+       mechanism, as #68's revealed controls. */
+    @media (hover: hover) and (pointer: fine) {
+      .track-row:hover {
+        background-color: var(--yj-hover-overlay, rgba(255, 255, 255, 0.05));
+      }
     }
 
     .track-row.selected {
@@ -1207,6 +1247,24 @@ export class TrackList
       background-color: var(--yj-selection-bg, rgba(100, 160, 255, 0.15));
     }
 
+    /* The press state (#54), and the only feedback a tap has now that
+       the web view's tap highlight is gone (index.css).
+
+       **Last, and as specific as the state rules above**: a row that
+       is selected and playing is .track-row.selected.active, so a
+       bare .track-row:active is one class short of it and a press
+       on the row a phone is most likely to press -- the one it just
+       selected -- would show nothing. Instant rather than
+       transitioned, because the only measured statement here about
+       transitions on a list is that two card grids removed theirs
+       for software-rendering repaint cost. */
+    .track-row.selected:active,
+    .track-row.active:active,
+    .track-row:active {
+      background-color: var(--yj-press-overlay, rgba(255, 255, 255, 0.12));
+    }
+
+
     .cell {
       overflow: hidden;
       text-overflow: ellipsis;
@@ -1303,6 +1361,11 @@ export class TrackList
             virt.removeEventListener('click', this.onDelegatedClick);
             virt.removeEventListener('dblclick', this.onDelegatedDblClick);
             virt.removeEventListener('contextmenu', this.onDelegatedContextMenu);
+            virt.removeEventListener('yj-tap', this.onRowTap);
+            virt.removeEventListener('yj-long-press', this.onRowLongPress);
+            virt.removeEventListener('yj-swipe-start', this.swipe.onSwipeStart);
+            virt.removeEventListener('yj-swipe-move', this.swipe.onSwipeMove);
+            virt.removeEventListener('yj-swipe-end', this.swipe.onSwipeEnd);
             virt.removeEventListener('dragstart', this.onDelegatedDragStart);
             virt.removeEventListener('dragend', this.onTrackDragEnd);
         }
@@ -1444,6 +1507,14 @@ export class TrackList
         virt.addEventListener('contextmenu', this.onDelegatedContextMenu);
         virt.addEventListener('dragstart', this.onDelegatedDragStart);
         virt.addEventListener('dragend', this.onTrackDragEnd);
+        // Delegated like the rest: the gesture layer dispatches on the
+        // element the finger landed on, composed, so it arrives here
+        // through the same path a real click takes (plan 019).
+        virt.addEventListener('yj-tap', this.onRowTap);
+        virt.addEventListener('yj-long-press', this.onRowLongPress);
+        virt.addEventListener('yj-swipe-start', this.swipe.onSwipeStart);
+        virt.addEventListener('yj-swipe-move', this.swipe.onSwipeMove);
+        virt.addEventListener('yj-swipe-end', this.swipe.onSwipeEnd);
         this.delegationAttached = true;
     }
 
@@ -1707,6 +1778,86 @@ export class TrackList
         if (hit) this.onTrackContextMenu(e, hit.track);
     };
 
+    /**
+     * A finger tapped a row (plan 019, #63).
+     *
+     * On a desktop a click selects and a double-click plays; a finger
+     * inverts that, because there is no second button and no modifier
+     * key, so the primary action has to be the primary gesture.
+     *
+     * Claiming the gesture (`preventDefault`) is what tells the layer
+     * to swallow the click behind it -- otherwise playing a track
+     * would also select it, and the row would end up in both states.
+     * A tap this does *not* claim falls through as an ordinary click,
+     * which is what keeps the favourite icon working.
+     */
+    private onRowTap = (e: GestureEvent) => {
+        const hit = this.resolveTrackFromEvent(e);
+
+        if (!hit) return;
+
+        // A control inside the row owns its own tap. The same rule the
+        // shortcut service has for a focused control that owns a key,
+        // and without it the 44px favourite target (#56) becomes a
+        // 44px play target.
+        if ((e.target as HTMLElement).closest('.fav-icon')) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+
+        if (this.selection.selectionMode) {
+            this.selection.toggleInMode(hit.track.FilePath, hit.index);
+            this.virtualizer?.requestUpdate();
+
+            return;
+        }
+
+        this.playFromRow(hit.index);
+    };
+
+    /**
+     * A finger held a row still for half a second.
+     *
+     * Claiming this is what makes it *selection mode* rather than the
+     * context menu it has been since plan 016 -- an unclaimed
+     * `yj-long-press` still becomes a `contextmenu`, which is how the
+     * card grids and Explore keep the behaviour they have.
+     */
+    private onRowLongPress = (e: GestureEvent) => {
+        const hit = this.resolveTrackFromEvent(e);
+
+        if (!hit) return;
+
+        e.preventDefault();
+        this.focusedIndex = hit.index;
+        this.selection.enterSelectionMode(hit.track.FilePath, hit.index);
+        this.virtualizer?.requestUpdate();
+    };
+
+    /**
+     * What a swipe on this row would queue.
+     *
+     * The same rule the context menu answers with, and it has to be:
+     * **one row is a position, several rows are an explicit choice.**
+     * A finger that swipes a row which is part of a selection of forty
+     * has not un-made that selection, and queueing the one row it
+     * touched would quietly contradict the bar above saying forty are
+     * selected. A swipe on a row *outside* the selection is a statement
+     * about that row, exactly as a right-click on one is -- and unlike
+     * a right-click it does not move the selection, because a swipe is
+     * not a way of selecting anything.
+     */
+    private swipeTargetKeys(filePath: string): string[] {
+        if (
+            this.selection.selectionCount > 1 &&
+            this.selection.isSelected(filePath)
+        ) {
+            return this.selection.getSelectedKeysOrdered();
+        }
+
+        return [filePath];
+    }
+
     private onDelegatedDragStart = (e: DragEvent) => {
         const hit = this.resolveTrackFromEvent(e);
 
@@ -1830,6 +1981,33 @@ export class TrackList
         emitDragActive(false);
     };
 
+    /**
+     * The row the menu can navigate from, for "Go to Artist" / "Go to
+     * Album" — which exist only below the phone breakpoint, where the
+     * row's own names are no longer links (#67).
+     *
+     * One row only, on the rule the Play item already states: one row
+     * is a position, several are an explicit choice of *those* tracks,
+     * and "go to the album" of five different albums means nothing.
+     */
+    private get goToTarget(): GoToTarget | undefined {
+        if (this.selection.selectionCount !== 1) return undefined;
+
+        const [path] = this.selection.selectedItems;
+        const track = path
+            ? tracksByFilePath(this.tracks).get(path)
+            : undefined;
+
+        if (!track) return undefined;
+
+        return {
+            artistName: track.ArtistName,
+            artistMBID: track.ArtistMBID,
+            albumName: track.Album,
+            albumMBID: track.ReleaseGroupMBID,
+        };
+    }
+
     private onContextMenuAction(action: string) {
         const filePaths =
             this.selection.getSelectedKeysOrdered();
@@ -2128,6 +2306,7 @@ export class TrackList
             'track-row': true,
             active,
             selected,
+            swiping: this.swipe.isSwiping(index),
         })}
         role="row"
         aria-rowindex=${index + 1}
@@ -2137,8 +2316,10 @@ export class TrackList
         draggable="true"
         data-index=${index}
         data-testid="track-row"
+        data-swipe
         data-file-path=${track.FilePath}
       >
+        ${this.swipe.renderReveal(index)}
         <div
           role="gridcell"
           class=${classMap({
@@ -2237,6 +2418,45 @@ export class TrackList
         this.saveSortPreferences();
     };
 
+    /**
+     * The three worth a thumb. Everything else is behind "More",
+     * which opens the context menu this list already renders.
+     *
+     * A bar is one row on a 424px screen and the menu is nine items,
+     * so this is a subset by necessity rather than a second opinion
+     * about what matters -- and plan 018's promise that no action is
+     * unreachable is kept by the overflow, not by this list.
+     */
+    private static readonly SELECTION_ACTIONS: SelectionAction[] = [
+        { id: 'play', label: 'Play', icon: ICON_PLAY },
+        { id: 'add-to-queue', label: 'Add to queue', icon: ICON_QUEUE },
+        { id: 'play-next', label: 'Play next', icon: ICON_PLAY_NEXT },
+    ];
+
+    private renderSelectionBar() {
+        // Only in selection mode: a mouse selection is modeless and
+        // shows its actions on right-click, which is where a desktop
+        // user looks for them.
+        if (!this.selection.selectionMode) return nothing;
+
+        return html`
+            <selection-bar
+                .count=${this.selection.selectionCount}
+                .actions=${TrackList.SELECTION_ACTIONS}
+                @selection-exit=${this.onSelectionExit}
+                @selection-action=${(e: CustomEvent<{ id: string }>) =>
+                    this.onContextMenuAction(e.detail.id)}
+                @selection-more=${(e: CustomEvent<{ x: number; y: number }>) =>
+                    this.ctxMenu.openAt(e.detail.x, e.detail.y)}
+            ></selection-bar>
+        `;
+    }
+
+    private onSelectionExit = () => {
+        this.selection.exitSelectionMode();
+        this.virtualizer?.requestUpdate();
+    };
+
     override render() {
         const visibleTracks = this.cachedSortedTracks;
         const cols = this.activeColumns;
@@ -2246,6 +2466,9 @@ export class TrackList
       <div class="sr-only" role="status" aria-live="polite">
         ${this.liveStatus(visibleTracks.length)}
       </div>
+      <div class="sr-only" role="status" aria-live="polite">
+        ${this.swipe.announcement}
+      </div>
       ${this.tracks.length === 0
                 ? this.renderPlaceholder()
                 : html`
@@ -2321,13 +2544,11 @@ export class TrackList
                     )}
       </div>
             </div>
+            ${this.renderSelectionBar()}
           `}
 
-      <wa-popup
+      <menu-surface
         id="context-menu"
-        placement="bottom-start"
-        flip
-        shift
         .active=${this.ctxMenu.contextMenuOpen}
       >
         ${this.ctxMenu.contextMenuOpen
@@ -2396,6 +2617,13 @@ export class TrackList
                     ></wa-icon>
                     Track Details
                 </wa-dropdown-item>
+                ${goToMenuItems(this.goToTarget, {
+                    onSelect: () => {
+                        this.selection.clear();
+                        this.ctxMenu.close();
+                    },
+                    onHover: () => this.ctxMenu.closePlaylistSubmenu(),
+                })}
                 <wa-dropdown-item
                     @click=${() =>
                         this.onContextMenuAction(
@@ -2413,13 +2641,12 @@ export class TrackList
               </div>
             `
                 : nothing}
-      </wa-popup>
+      </menu-surface>
 
-      <wa-popup
+      <menu-surface
         id="playlist-submenu"
+                label="Add to playlist"
         placement="right-start"
-        flip
-        shift
         .active=${this.ctxMenu.playlistSubmenuOpen}
       >
         ${this.ctxMenu.playlistSubmenuOpen && this.selection.hasSelection
@@ -2437,7 +2664,7 @@ export class TrackList
               </div>
             `
                 : nothing}
-      </wa-popup>
+      </menu-surface>
 
       <track-details></track-details>
     `;

frontend/src/store/theme-store.ts

@@ -46,6 +46,17 @@ export interface ShadePalette {
     border: string;
     borderSubtle: string;
     hoverOverlay: string;
+    /**
+     * The tint a surface takes while it is being pressed (#54).
+     *
+     * Separate from `hoverOverlay` because the two answer different
+     * questions and only one of them a phone can ask: a hover is a
+     * pointer resting somewhere, a press is a finger on the thing it
+     * is about to activate. It is deliberately the stronger of the
+     * two — a press that reads the same as a hover says nothing on a
+     * device where the hover is synthesised by the press itself.
+     */
+    pressOverlay: string;
     selectionBg: string;
 }
 
@@ -95,6 +106,7 @@ export const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
         border: '#333333',
         borderSubtle: '#222222',
         hoverOverlay: 'rgba(255, 255, 255, 0.05)',
+        pressOverlay: 'rgba(255, 255, 255, 0.12)',
         selectionBg: 'rgba(100, 160, 255, 0.15)',
     },
     dark: {
@@ -114,6 +126,7 @@ export const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
         border: '#444444',
         borderSubtle: '#333333',
         hoverOverlay: 'rgba(255, 255, 255, 0.05)',
+        pressOverlay: 'rgba(255, 255, 255, 0.12)',
         selectionBg: 'rgba(100, 160, 255, 0.15)',
     },
     light: {
@@ -133,6 +146,7 @@ export const SHADE_PALETTES: Record<BackgroundShade, ShadePalette> = {
         border: '#ced4da',
         borderSubtle: '#dee2e6',
         hoverOverlay: 'rgba(0, 0, 0, 0.05)',
+        pressOverlay: 'rgba(0, 0, 0, 0.12)',
         selectionBg: 'rgba(100, 160, 255, 0.15)',
     },
 };
@@ -285,6 +299,7 @@ function deriveThemeVariables(
 
         // Interactive overlays
         '--yj-hover-overlay': palette.hoverOverlay,
+        '--yj-press-overlay': palette.pressOverlay,
         '--yj-selection-bg': palette.selectionBg,
 
         // Semantic *fills* — the background of a solid button or badge.

frontend/src/store/volume-style-store.ts

@@ -1,5 +1,6 @@
 import { EventsOn } from '@runtime/runtime';
 import { GetPopupVolume } from '@go/config/config.js';
+import { SystemOwnsVolume } from '@go/player/player.js';
 import { Events } from '../events';
 
 type Subscriber = () => void;
@@ -28,10 +29,37 @@ type Subscriber = () => void;
  * becomes one. An install that has chosen the popup sees it swap once
  * on load, which is the cheaper of the two wrong first frames: the
  * inline slider occupies the space the popup's button would have.
+ *
+ * **`available` is the question one step earlier — whether there is a
+ * volume of ours to draw at all (#64).** On Android the hardware keys
+ * are the volume control and the backend pins its own level at
+ * maximum, so a slider here would move nothing.
+ *
+ * It is asked of the *player* rather than of the viewport, and that is
+ * the whole design decision. Every other stand-down rule in this app
+ * is a width, because a width is what a browser can answer and what
+ * every tier can test — but this one is a property of the build. Keyed
+ * on width instead, an Android tablet at 600px or more would draw the
+ * bottom bar's slider over a pinned level: a control that cannot act,
+ * which `library-status-indicator` settled is worse than none.
+ *
+ * It lives beside `popup` because both answer "what presentation does
+ * the volume control get", both readers are the same two components,
+ * and "none" is a presentation. A second store would be a second
+ * subscription in the same `connectedCallback` saying the same thing.
+ *
+ * The initial value is `true` on the same first-frame rule: there is a
+ * volume on every platform but one, and the platform that pins it sees
+ * the control once at boot and never again in the session — the answer
+ * cannot change while the app runs, so by the time the lazily-mounted
+ * now-playing view exists it has long been settled by the bar's own
+ * copy.
  */
 class VolumeStyleStore {
     private value = false;
 
+    private hasVolume = true;
+
     private loaded = false;
 
     private subscribers = new Set<Subscriber>();
@@ -47,13 +75,21 @@ class VolumeStyleStore {
         return this.value;
     }
 
+    /**
+     * Whether this app has a volume of its own to control. False where
+     * the device owns it; see the class comment.
+     */
+    get available(): boolean {
+        return this.hasVolume;
+    }
+
     /** Reads the setting once. Safe to call from every mount. */
     async init(): Promise<void> {
         if (this.loaded) return;
 
         this.loaded = true;
 
-        await this.refresh();
+        await Promise.all([this.refreshAvailability(), this.refresh()]);
     }
 
     subscribe(fn: Subscriber): () => void {
@@ -77,6 +113,28 @@ class VolumeStyleStore {
         }
     }
 
+    /**
+     * Asked once, not on `GeneralConfigChanged`: this is a property of
+     * the platform the binary was built for and cannot change while
+     * the app is running.
+     */
+    private async refreshAvailability(): Promise<void> {
+        try {
+            const owned = await SystemOwnsVolume();
+
+            if (owned === !this.hasVolume) return;
+
+            this.hasVolume = !owned;
+            this.notify();
+        } catch (err) {
+            // The control renders, which is the answer on every
+            // platform but one and is the recoverable way to be wrong:
+            // a working control nobody needs, rather than a missing one
+            // somebody does.
+            console.error('failed to ask who owns the volume', err);
+        }
+    }
+
     private notify(): void {
         for (const fn of this.subscribers) fn();
     }

frontend/src/styles/back-button.css.ts

@@ -0,0 +1,54 @@
+import { css } from 'lit';
+
+/**
+ * The way out of a detail view, at the app's 44px touch floor.
+ *
+ * #186's second table names `artist-details`' back button at
+ * **32x32**. It is the same declaration in **six** components —
+ * `artist-details`, `genre-details`, `playlist-details`,
+ * `smart-playlist-details`, `explore-artist-details` and
+ * `explore-album-details` — byte-identical, 32px in all six, and the
+ * sweep that filed the issue visited one of them.
+ *
+ * That is the argument for this file rather than six edits. A device
+ * sweep walks the views somebody thought to open, so six copies of a
+ * control is six chances for the next pass to miss five; the arrows
+ * and the toggles were each one declaration covering 36 and 29
+ * controls, and this is the same shape stated the other way round.
+ *
+ * **It is a real 44px box, not padding with the width handed back.**
+ * The header pass had to grow a hit area past its own layout box
+ * because `page-header` measures itself for #69's overflow fit; a
+ * detail view's header does not, so the control can simply be the
+ * target. It also *should* be — this button has a visible background,
+ * so a hit area larger than the circle would be a control that is
+ * bigger than it looks, which is the thing #187 accepts only where a
+ * thin painted track is the point.
+ *
+ * The size is #55's, arrived at for the same reason one component
+ * over: "the way out is 44px on a phone", when the queue panel's close
+ * button was 25x21 and, at phone width, the only pointer route off a
+ * full-screen surface. A detail view has the platform's back gesture
+ * as well, so this is less severe than the queue was — it is the same
+ * control wearing the same mistake.
+ */
+export const backButton = css`
+    .back-button {
+        display: flex;
+        align-items: center;
+        justify-content: center;
+        width: 44px;
+        height: 44px;
+        border: none;
+        border-radius: 50%;
+        background: var(--yj-bg-overlay, rgba(255, 255, 255, 0.06));
+        color: var(--yj-text-primary, #fff);
+        cursor: pointer;
+        flex-shrink: 0;
+        transition: background-color 0.15s ease;
+    }
+
+    .back-button:hover {
+        background: var(--yj-bg-hover, rgba(255, 255, 255, 0.12));
+    }
+`;

frontend/src/styles/wa-touch-floor.css.ts

@@ -0,0 +1,48 @@
+import { css } from 'lit';
+
+/**
+ * A Web Awesome form control is at least the app's 44px touch floor.
+ *
+ * #56 named 44px and #186 found nothing but the transport had reached
+ * it. Web Awesome's form controls are the part of Settings this app
+ * does not draw: measured on the reference device (TLP301, 424x439),
+ * `wa-input`'s control is **204x20** and `wa-button` **185x21** — the
+ * shortest controls on the page, and the only ones whose height is
+ * decided inside somebody else's shadow root.
+ *
+ * `--wa-form-control-height` is that decision, and it is the library's
+ * own theming variable rather than a part or an internal — the default
+ * theme sets it at `:root` and every control that has a height reads
+ * it (button, input, select, radio). So this is `wa-slider-label`'s
+ * better half: the API first, and no reach into a shadow root at all.
+ *
+ * Three things about it are load-bearing.
+ *
+ * **A custom property inherits through a shadow boundary**, which is
+ * what lets a `:host` declaration reach a `wa-input` the host renders.
+ * That is also why it is a stylesheet a component adopts rather than a
+ * `:root` rule in `index.css`: a `:root` rule would cover every wa
+ * control in the app in one line and be invisible to the component
+ * tier, which renders a component and no page stylesheet. Here the
+ * floor is measurable where it is applied.
+ *
+ * **It is a flat 44px rather than a floor over the library's own
+ * expression.** The default is `round(calc(2 * padding-block + 1em *
+ * line-height), 1px)` — em-based, so `size="small"` is what produced
+ * the 20px above — and a `max(44px, …)` would have to restate that
+ * formula here, which is a copy of somebody else's arithmetic that
+ * goes stale silently. A flat value is safe because this app uses
+ * exactly two sizes, `small` and the default, and both are under the
+ * floor; a `size="large"` added later would be pinned down to 44 and
+ * should take that as the prompt to revisit this.
+ *
+ * **Only the height is pinned.** The font size still comes from
+ * `size="small"`, so a control grows its hit area without growing its
+ * visual weight — which is what #186's Direction asks for and what the
+ * page header's second pass had to be corrected to do.
+ */
+export const waTouchFloor = css`
+    :host {
+        --wa-form-control-height: 44px;
+    }
+`;

frontend/src/utils/context-menu-controller.ts

@@ -5,7 +5,20 @@ import type {
 } from 'lit';
 import type WaPopup from '@awesome.me/webawesome/dist/components/popup/popup.js';
 
+/**
+ * What this controller needs of a surface: something it can switch on
+ * and point at. Both `wa-popup` and `menu-surface` satisfy it.
+ */
+export type MenuTarget = HTMLElement & {
+    active: boolean;
+    anchor?: WaPopup['anchor'];
+};
+
 import { registerViewAware } from './view-lifecycle';
+import {
+    MENU_DISMISS_EVENT,
+    MENU_SHOWN_EVENT,
+} from '../components/menu-surface/menu-surface';
 
 /**
  * Host interface for components using the ContextMenuController.
@@ -17,10 +30,18 @@ export interface ContextMenuHost
     extends ReactiveControllerHost {
     updateComplete: Promise<boolean>;
     shadowRoot: ShadowRoot | null;
-    /** Return the main context-menu popup element. */
+    /**
-    getContextMenuPopup(): WaPopup | undefined;
+     * Return the main context-menu surface.
-    /** Return the playlist submenu popup element. */
+     *
-    getPlaylistSubmenuPopup(): WaPopup | undefined;
+     * `MenuSurface` since #60, which is a `wa-popup` above 600px and a
+     * bottom sheet below it. The type is the narrow shape this
+     * controller drives rather than either element, so a host that
+     * still renders a bare `wa-popup` — the playlist submenu does —
+     * satisfies it unchanged.
+     */
+    getContextMenuPopup(): MenuTarget | undefined;
+    /** Return the playlist submenu surface. */
+    getPlaylistSubmenuPopup(): MenuTarget | undefined;
     /**
      * Called when the context menu is closed by an
      * outside click/contextmenu/mousedown.  Components
@@ -33,6 +54,15 @@ export interface ContextMenuHost
 /** Submenu close delay in milliseconds. */
 const SUBMENU_CLOSE_DELAY = 150;
 
+/**
+ * How long to keep trying to put focus on a menu's first item.
+ *
+ * Long enough to outlast `wa-dialog`'s show animation, which ends by
+ * focusing the dialog; short enough that a menu which genuinely has no
+ * items stops rather than spinning for the life of the page.
+ */
+const FOCUS_RETRY_BUDGET_MS = 500;
+
 /** A menu item, focusable and clickable. Web Awesome sets `role` itself. */
 type MenuItem = HTMLElement & { active?: boolean; disabled?: boolean };
 
@@ -73,6 +103,30 @@ export class MenuKeyboard {
         void this.focusFirstItem(panel);
     }
 
+    /**
+     * Take focus back, for a surface that finished showing after we
+     * had already placed it.
+     *
+     * `wa-dialog` focuses `[autofocus]` or *itself* on the animation
+     * frame after `showModal()`, and it cannot see our first menu item
+     * to prefer it: the panel is slotted through `menu-surface`, so the
+     * dialog's own `querySelector` stops at the `<slot>`. Retrying on a
+     * longer budget does not fix this either -- the first attempt
+     * *succeeds*, and the steal happens afterwards. Measured on the
+     * device: the sheet opened with focus on the `<dialog>` and every
+     * arrow key went nowhere.
+     *
+     * So the surface says when it has settled and this re-asserts. It
+     * is a no-op for a menu that is closed or that already has focus.
+     */
+    refocus(): void {
+        const panel = this.panel;
+
+        if (!panel || panel.contains(deepActiveElement())) return;
+
+        void this.focusFirstItem(panel);
+    }
+
     /**
      * Focus the first item, once the items are items.
      *
@@ -91,11 +145,24 @@ export class MenuKeyboard {
 
         await Promise.all(candidates.map((el) => el.updateComplete ?? null));
 
-        // …and once the popup has positioned itself. `wa-popup` places the
+        // …and once the surface has shown itself. `wa-popup` places the
         // panel on an animation frame, and `focus()` on a not-yet-shown
         // element is a silent no-op — which looks identical to a menu
         // that opened and refused to take focus.
-        for (let attempt = 0; attempt < 3; attempt++) {
+        //
+        // **The budget is time, not frames, because #60 gave this a
+        // second kind of surface.** Three frames was enough for a
+        // popup; a `wa-dialog` runs a show *animation* and moves focus
+        // to the dialog itself when it finishes, which lands after
+        // those frames and takes the focus back. Measured on the
+        // device: the sheet opened with `document.activeElement` on the
+        // `<dialog>`, so every arrow key went nowhere. Retrying to a
+        // deadline is `roving-grid`'s rule for the same reason — the
+        // thing being waited for is another component's animation, not
+        // a fixed number of paints.
+        const deadline = Date.now() + FOCUS_RETRY_BUDGET_MS;
+
+        while (Date.now() < deadline) {
             // Bail if the menu closed while we waited.
             if (this.panel !== panel) return;
 
@@ -259,6 +326,20 @@ export class ContextMenuController
     /** Bound close handler for document events. */
     private closeHandler = () => this.close();
 
+    /**
+     * A surface finished showing; see `MenuKeyboard.refocus`.
+     *
+     * **Not while the submenu is up.** Both surfaces send this, and the
+     * submenu's sheet opens *over* the main one -- so re-asserting
+     * focus on the main panel's first item would snatch it straight
+     * back out of the playlist picker the user just opened.
+     */
+    private shownHandler = () => {
+        if (this.contextMenuOpen && !this.playlistSubmenuOpen) {
+            this.keyboard.refocus();
+        }
+    };
+
     /** Bound mousedown handler for outside-click detection. */
     private mousedownCloseHandler = (
         e: MouseEvent,
@@ -325,12 +406,28 @@ export class ContextMenuController
             'mousedown',
             this.mousedownCloseHandler,
         );
+        document.addEventListener(
+            MENU_DISMISS_EVENT,
+            this.closeHandler,
+        );
+        document.addEventListener(
+            MENU_SHOWN_EVENT,
+            this.shownHandler,
+        );
     }
 
     private detach(): void {
         if (!this.listening) return;
 
         this.listening = false;
+        document.removeEventListener(
+            MENU_DISMISS_EVENT,
+            this.closeHandler,
+        );
+        document.removeEventListener(
+            MENU_SHOWN_EVENT,
+            this.shownHandler,
+        );
         document.removeEventListener(
             'click',
             this.closeHandler,
@@ -550,6 +647,48 @@ export const contextMenuStyles = css`
         z-index: 200;
     }
 
+    /* ---------------------------------------------------------------
+       The sheet (#60).
+
+       menu-surface puts data-sheet on the panel when it is drawn
+       as a bottom sheet, and these rules are here rather than in that
+       component because the panel is the *host's* light DOM: it lives
+       in the host's shadow root, so only the host's stylesheet can
+       reach it. This file is the one every call site already includes,
+       which is what makes twelve menus grow thumb-sized rows from one
+       edit.
+
+       Measured on the device before the change: rows were 29px, against
+       the 44px floor plan 018 promises and the 48px this issue asks
+       for. --------------------------------------------------------- */
+    .context-menu-panel[data-sheet] {
+        border: none;
+        border-radius: 0;
+        box-shadow: none;
+        min-width: 0;
+        padding: 4px 0 8px;
+        background-color: transparent;
+    }
+
+    .context-menu-panel[data-sheet] wa-dropdown-item {
+        font-size: var(--yj-text-md, 0.9375rem);
+        min-height: 48px;
+        align-items: center;
+    }
+
+    .context-menu-panel[data-sheet] wa-dropdown-item::part(base) {
+        min-height: 48px;
+        align-items: center;
+    }
+
+    /* A submenu arrow means "a flyout opens to the right", which is not
+       what happens on a phone and is not a thing a thumb can aim at.
+       The row still works — it is the tap handler that opens the
+       playlist picker — so what goes is the arrow, not the item. */
+    .context-menu-panel[data-sheet] .submenu-arrow {
+        display: none;
+    }
+
     .context-menu-panel {
         background-color: var(
             --yj-bg-elevated,
@@ -571,10 +710,35 @@ export const contextMenuStyles = css`
         font-size: 13px;
     }
 
-    .context-menu-panel wa-dropdown-item:hover {
+    /* A hover tint is for a device that hovers (#54).
+
+       Below the query is a phone, where a hold *synthesises* a hover
+       in the WebView -- the same mechanism #68 gates the revealed
+       controls on -- so an ungated tint is a highlight that arrives
+       because a finger touched the row and then stays on it after the
+       finger has gone. Which is indistinguishable from the press
+       state below, and outlives it. */
+    @media (hover: hover) and (pointer: fine) {
+        .context-menu-panel wa-dropdown-item:hover {
+            background-color: var(
+                --yj-hover-overlay,
+                rgba(255, 255, 255, 0.1)
+            );
+        }
+    }
+
+    /* And a press state is for every device, because it is the one
+       piece of feedback a tap has now that the web view's own
+       highlight box is gone (index.css). Stronger than the hover tint
+       on purpose, and instant rather than transitioned: the only
+       measured statement this repo has about transitions on these
+       surfaces is the two card grids that removed theirs because
+       software rendering repaints per frame, and the phone is not
+       something this session can measure. */
+    .context-menu-panel wa-dropdown-item:active {
         background-color: var(
-            --yj-hover-overlay,
+            --yj-press-overlay,
-            rgba(255, 255, 255, 0.1)
+            rgba(255, 255, 255, 0.12)
         );
     }
 

frontend/src/utils/explore-link.ts

@@ -13,11 +13,35 @@
  * bug, not as a statement about metadata.  The only case that still
  * renders as text is one we genuinely cannot route (no name at all, or
  * nothing in the library by that name).
+ *
+ * ## Below the phone breakpoint a name is not a link (#67)
+ *
+ * A few characters of text inside a row is not a touch target, and the
+ * click handling below is explicitly a *desktop* compromise: the
+ * navigation is held for one double-click interval so double-clicking
+ * the row can still play it, which means nothing at all on touch.  On
+ * a phone the row's own gesture wins anyway — a claimed `yj-tap` has
+ * its click swallowed by `utils/touch-gestures.ts`, so the link was
+ * unreachable as well as fiddly.
+ *
+ * So the rule lives here rather than at twenty call sites, which is
+ * what the Findings on #67 ask for: a name renders as plain text below
+ * `PHONE_QUERY`, and the row's context menu carries "Go to Artist" /
+ * "Go to Album" in its place (`goToMenuItems`).
+ *
+ * The exception is `keepOnPhone`, and it is not a preference.  Three
+ * surfaces render a name with **no menu to carry the destination** —
+ * `now-playing-view`, `explore-album-details`' header credit and
+ * `top-results-row` — so suppressing the link there takes the action
+ * away entirely rather than moving it, which is what plan 018's "no
+ * action is unreachable at any supported size" refuses.  Each of those
+ * call sites says so.
  */
 
 import { html, css } from 'lit';
 import type { TemplateResult } from 'lit';
 import { libraryStore } from '../store/library-store';
+import { PHONE_QUERY } from './breakpoints';
 
 /** Shared CSS for explore link styling. Import into component styles. */
 export const exploreLinkStyles = css`
@@ -32,6 +56,57 @@ export const exploreLinkStyles = css`
     }
 `;
 
+/**
+ * Options every link function takes, for the one case that is not the
+ * default.
+ */
+export interface LinkOptions {
+    /**
+     * Keep the name navigable at phone width.
+     *
+     * For a surface with no context menu to carry the destination —
+     * see the header of this file.  A row must not pass it: the row's
+     * tap already means "play", and the menu is where the destination
+     * went.
+     */
+    keepOnPhone?: boolean;
+}
+
+/**
+ * The live phone breakpoint, made once and read per link.
+ *
+ * A `MediaQueryList` is live, so one object answers for the life of
+ * the page and a resize needs nothing from here.  The identity check
+ * is the test seam: this tier's viewport is fixed by the runner, so a
+ * spec answers the query by replacing `window.matchMedia` (the same
+ * stub `now-playing-phone.test.ts` installs), and swapping the
+ * function is what tells us to ask again.
+ */
+let phoneQuery: MediaQueryList | undefined;
+let phoneQuerySource: typeof window.matchMedia | undefined;
+
+/**
+ * Whether an inline name still navigates.
+ *
+ * Exported because the menus that carry the destination in its place
+ * are drawn under exactly the same condition -- one answer, not two.
+ */
+export function inlineLinksSuppressed(): boolean {
+    if (!window.matchMedia) return false;
+
+    if (phoneQuerySource !== window.matchMedia) {
+        phoneQuerySource = window.matchMedia;
+        phoneQuery = window.matchMedia(PHONE_QUERY);
+    }
+
+    return phoneQuery?.matches ?? false;
+}
+
+/** Whether this call site should render plain text rather than a link. */
+function plainText(options?: LinkOptions): boolean {
+    return !options?.keepOnPhone && inlineLinksSuppressed();
+}
+
 /** Fire a navigate event from the clicked element. */
 function navigate(target: EventTarget, detail: Record<string, unknown>): void {
     target.dispatchEvent(
@@ -153,39 +228,19 @@ function singleClick(
  * @param mbid - The MusicBrainz artist ID.  Empty string = local only.
  * @param content - Optional custom content to render inside the link
  *                  (e.g. highlighted search result).  Defaults to artistName.
+ * @param options - See `LinkOptions`.
  */
 export function artistLink(
     artistName: string,
     mbid: string,
     content?: TemplateResult | string,
+    options?: LinkOptions,
 ): TemplateResult | string {
     if (!artistName) return artistName;
+    if (plainText(options)) return content ?? artistName;
 
     const onClick = singleClick((target) => {
-        void (async () => {
+        void openArtistPage(target, artistName, mbid);
-            if (mbid) {
-                navigate(target, {
-                    view: 'explore-artist-details',
-                    artistMBID: mbid,
-                    artistName,
-                });
-
-                return;
-            }
-
-            const local = await findLocalArtist(artistName);
-            if (!local) return;
-
-            // The caller's row had no MBID, but the library row for the
-            // same artist may — the grid routes by exactly this field,
-            // so reading it here is what keeps the two paths agreeing.
-            navigate(target, {
-                view: 'explore-artist-details',
-                artistMBID: local.MBID || '',
-                artistName,
-                localArtistId: local.ID,
-            });
-        })();
     });
 
     return html`<a
@@ -203,19 +258,22 @@ export function artistLink(
  * @param mbid - The MusicBrainz release group ID.  Empty = local only.
  * @param content - Optional custom content to render inside the link.
  * @param artistName - Disambiguates same-named albums in the library.
+ * @param options - See `LinkOptions`.
  */
 export function albumLink(
     albumName: string,
     mbid: string,
     content?: TemplateResult | string,
     artistName?: string,
+    options?: LinkOptions,
 ): TemplateResult | string {
     if (!albumName) return albumName;
+    if (plainText(options)) return content ?? albumName;
 
     return html`<a
         class="explore-link"
         @click=${singleClick((target) => {
-            void openAlbum(target, albumName, mbid, artistName);
+            void openAlbumPage(target, albumName, mbid, artistName);
         })}
         title=${mbid ? 'View album on Explore' : 'View album in your library'}
     >${content ?? albumName}</a>`;
@@ -232,6 +290,7 @@ export function albumLink(
  * @param recordingMBID - The track's MusicBrainz recording ID.
  * @param content - Optional custom content (e.g. highlighted text).
  * @param artistName - Disambiguates same-named albums in the library.
+ * @param options - See `LinkOptions`.
  */
 export function trackLink(
     trackName: string,
@@ -240,14 +299,16 @@ export function trackLink(
     recordingMBID: string,
     content?: TemplateResult | string,
     artistName?: string,
+    options?: LinkOptions,
 ): TemplateResult | string {
     if (!trackName) return trackName;
     if (!albumName) return content ?? trackName;
+    if (plainText(options)) return content ?? trackName;
 
     return html`<a
         class="explore-link"
         @click=${singleClick((target) => {
-            void openAlbum(
+            void openAlbumPage(
                 target,
                 albumName,
                 releaseGroupMBID,
@@ -262,11 +323,48 @@ export function trackLink(
     >${content ?? trackName}</a>`;
 }
 
+/**
+ * Route to an artist page, preferring the catalog and falling back to
+ * the library copy.
+ *
+ * Exported because a menu item goes to the same place a name does, and
+ * two routings of "go to this artist" is how the two come to disagree
+ * about an untagged one.
+ */
+export async function openArtistPage(
+    target: EventTarget,
+    artistName: string,
+    mbid: string,
+): Promise<void> {
+    if (mbid) {
+        navigate(target, {
+            view: 'explore-artist-details',
+            artistMBID: mbid,
+            artistName,
+        });
+
+        return;
+    }
+
+    const local = await findLocalArtist(artistName);
+    if (!local) return;
+
+    // The caller's row had no MBID, but the library row for the
+    // same artist may — the grid routes by exactly this field,
+    // so reading it here is what keeps the two paths agreeing.
+    navigate(target, {
+        view: 'explore-artist-details',
+        artistMBID: local.MBID || '',
+        artistName,
+        localArtistId: local.ID,
+    });
+}
+
 /**
  * Route to an album page, preferring the catalog and falling back to
  * the library copy.  `highlight*` marks one track on arrival.
  */
-async function openAlbum(
+export async function openAlbumPage(
     target: EventTarget,
     albumName: string,
     releaseGroupMBID: string,
@@ -337,23 +435,31 @@ export interface CreditPart {
  * @param parts - The credit's parts in position order, if known.
  * @param fallbackName - The credit as a single string.
  * @param fallbackMbid - The primary artist's MBID.
+ * @param options - See `LinkOptions`.
  */
 export function creditLink(
     parts: readonly CreditPart[] | undefined,
     fallbackName: string,
     fallbackMbid: string,
+    options?: LinkOptions,
 ): TemplateResult | string {
     // One part is one link, so it is the fallback rather than a special
     // case — and a zero-part credit reaching here would otherwise
     // render as nothing at all, which is worse than the single-artist
     // answer it replaced.
     if (!parts || parts.length < 2) {
-        return artistLink(fallbackName, fallbackMbid);
+        return artistLink(fallbackName, fallbackMbid, undefined, options);
     }
 
+    // A decomposed credit is rendered from the same parts either way,
+    // so the join phrases survive the suppression and the text reads
+    // as it did — which is `creditText`'s job, and it is the string
+    // the `title=` beside these already uses.
+    if (plainText(options)) return creditText(parts, fallbackName);
+
     return html`${parts.map(
         (part) =>
-            html`${artistLink(part.creditedName, part.artistMbid)}${part.joinPhrase}`,
+            html`${artistLink(part.creditedName, part.artistMbid, undefined, options)}${part.joinPhrase}`,
     )}`;
 }
 

frontend/src/utils/go-to-menu.ts

@@ -0,0 +1,109 @@
+/**
+ * "Go to Artist" / "Go to Album", for the menus that carry a name the
+ * phone stopped drawing as a link (#67).
+ *
+ * `utils/explore-link.ts` renders a plain string below the phone
+ * breakpoint, because a few characters inside a row is not a touch
+ * target and the row's own tap already means "play".  That takes a
+ * destination away, so the row's context menu gives it back — which is
+ * the whole of this issue: the navigation moves, it does not go.
+ *
+ * Three things about it are load-bearing.
+ *
+ * **It is drawn under exactly the condition the link is not.**
+ * `inlineLinksSuppressed()` answers both, so a desktop menu is
+ * untouched (the name beside it is still a link, and a menu that
+ * repeats what the row already offers is furniture) and a phone menu
+ * cannot be missing what the row lost.
+ *
+ * **It goes where the name went.** `openArtistPage` / `openAlbumPage`
+ * are `explore-link`'s own routing, exported rather than reimplemented,
+ * so an untagged artist reaches the library page here for the same
+ * reason and by the same lookup it does from a link.
+ *
+ * **The host says when it is over**, through `onSelect` — every menu in
+ * this app closes itself and most clear their selection, and both are
+ * the host's bookkeeping rather than something a shared item may do on
+ * its behalf.  `onHover` is for the four hosts with a playlist submenu,
+ * which closes on any other item being pointed at.
+ */
+
+import { html, nothing } from 'lit';
+import type { TemplateResult } from 'lit';
+
+import { inlineLinksSuppressed, openArtistPage, openAlbumPage } from './explore-link';
+
+/**
+ * The entities one row or card can send you to.
+ *
+ * Everything is optional because the hosts differ: a track row knows
+ * both, an album card knows only its artist, and an artist page's own
+ * tracklist knows only the album.
+ */
+export interface GoToTarget {
+    artistName?: string;
+    artistMBID?: string;
+    albumName?: string;
+    albumMBID?: string;
+}
+
+export interface GoToHandlers {
+    /** Called before navigating: close the menu, clear the selection. */
+    onSelect?: () => void;
+    /** Called on hover: close a playlist submenu, where the host has one. */
+    onHover?: () => void;
+}
+
+/**
+ * The menu items for a target, or nothing at all where the name beside
+ * them is still a link.
+ */
+export function goToMenuItems(
+    target: GoToTarget | undefined,
+    handlers: GoToHandlers = {},
+): TemplateResult | typeof nothing {
+    if (!target || !inlineLinksSuppressed()) return nothing;
+
+    const artist = target.artistName?.trim();
+    const album = target.albumName?.trim();
+
+    if (!artist && !album) return nothing;
+
+    return html`
+        ${artist
+            ? html`<wa-dropdown-item
+                  data-testid="go-to-artist"
+                  @click=${(e: Event) => {
+                      handlers.onSelect?.();
+                      void openArtistPage(
+                          e.currentTarget as EventTarget,
+                          artist,
+                          target.artistMBID ?? '',
+                      );
+                  }}
+                  @mouseenter=${() => handlers.onHover?.()}
+              >
+                  <wa-icon slot="icon" name="user-group"></wa-icon>
+                  Go to Artist
+              </wa-dropdown-item>`
+            : nothing}
+        ${album
+            ? html`<wa-dropdown-item
+                  data-testid="go-to-album"
+                  @click=${(e: Event) => {
+                      handlers.onSelect?.();
+                      void openAlbumPage(
+                          e.currentTarget as EventTarget,
+                          album,
+                          target.albumMBID ?? '',
+                          artist,
+                      );
+                  }}
+                  @mouseenter=${() => handlers.onHover?.()}
+              >
+                  <wa-icon slot="icon" name="compact-disc"></wa-icon>
+                  Go to Album
+              </wa-dropdown-item>`
+            : nothing}
+    `;
+}

frontend/src/utils/long-press.ts

@@ -1,201 +0,0 @@
-/**
- * Long-press as the touch equivalent of a right-click (plan 016 B2,
- * phase 3).
- *
- * Every context menu in the app opens from a `contextmenu` event —
- * `track-list` and `queue-panel` delegate one on their virtualizer,
- * the card grids and both playlist detail views bind one per row, and
- * `explore-artist-details` binds three. A phone has no right-click, so
- * a phone reached none of them.
- *
- * **This is one document listener, not six components' worth of touch
- * handling.** A press that stays still for `LONG_PRESS_MS` dispatches a
- * synthetic `contextmenu` at the touch point on the element the touch
- * actually landed on, and every existing handler — delegated or
- * per-row, in any shadow root — runs unchanged. Six implementations of
- * a gesture is exactly the fault `ContextMenuController` exists to
- * prevent, and a seam that needs no component to opt in cannot be
- * forgotten by the next component.
- *
- * Three things about it are load-bearing.
- *
- * **The target comes from `composedPath()[0]`, not from
- * `elementFromPoint`**, which stops at the outermost shadow host: every
- * menu in this app is bound inside one, so a synthetic event dispatched
- * on the host reaches a delegated listener and no per-row one.
- *
- * **A browser that already does this must win.** Chromium fires a
- * `contextmenu` on long-press itself; WebKitGTK and the Android WebView
- * vary. So one arriving during the press cancels ours, and one arriving
- * just after ours is swallowed at document capture — where nothing else
- * has seen it yet. The two are told apart by **identity** (a `WeakSet`
- * of the events this module made) rather than by `isTrusted`, so the
- * suppressor cannot eat the event it exists to deliver, the rule holds
- * for anything else in the app that synthesises one, and a test can
- * stand in for a browser that fires its own.
- *
- * **The click that ends the gesture is swallowed.** A row's click
- * selects, and a card's plays; without this, opening a menu also
- * activates the thing under it. It is keyed on the gesture (cleared by
- * the next `pointerdown`) rather than on a time window, so a quick tap
- * on the menu that just opened is not eaten too.
- */
-
-/** How long a press must hold still to mean "menu". */
-export const LONG_PRESS_MS = 500;
-
-/**
- * How far a press may drift and still count. Below a finger's own
- * jitter is a gesture nobody can perform; above ~12px it starts
- * stealing the first frames of a scroll.
- */
-export const MOVE_TOLERANCE_PX = 10;
-
-/** The active installation, so a second call is a no-op rather than a
- *  second listener set. */
-let uninstall: (() => void) | null = null;
-
-/** The events this module dispatched. Identity, not `isTrusted`: see
- *  the note above. */
-const ours = new WeakSet<Event>();
-
-/**
- * Install the gesture. Idempotent; returns the uninstaller (which the
- * tests use — the app installs once and never removes it).
- */
-export function installLongPressContextMenu(): () => void {
-    if (uninstall) return uninstall;
-
-    let timer: ReturnType<typeof setTimeout> | null = null;
-    let originX = 0;
-    let originY = 0;
-    let target: EventTarget | null = null;
-
-    /** A trusted `contextmenu` arrived for this press: the browser has
-     *  it covered. */
-    let nativeSeen = false;
-
-    /** We opened a menu, and the click ending that gesture is not a
-     *  click on anything. */
-    let swallowClick = false;
-
-    /** We dispatched one, so a trusted one arriving now is a duplicate. */
-    let justFired = false;
-
-    const cancel = (): void => {
-        if (timer !== null) clearTimeout(timer);
-
-        timer = null;
-        target = null;
-    };
-
-    const fire = (): void => {
-        timer = null;
-
-        const el = target;
-
-        target = null;
-
-        if (nativeSeen || !el) return;
-
-        justFired = true;
-        swallowClick = true;
-
-        const menu = new MouseEvent('contextmenu', {
-            bubbles: true,
-            cancelable: true,
-            // Or it stops at the shadow root the row lives in, and the
-            // delegated listeners never see it.
-            composed: true,
-            clientX: originX,
-            clientY: originY,
-            button: 2,
-        });
-
-        ours.add(menu);
-        el.dispatchEvent(menu);
-    };
-
-    const onPointerDown = (e: PointerEvent): void => {
-        // A new gesture: whatever the last one left behind is stale.
-        swallowClick = false;
-        justFired = false;
-        nativeSeen = false;
-        cancel();
-
-        if (e.pointerType !== 'touch' || !e.isPrimary) return;
-
-        originX = e.clientX;
-        originY = e.clientY;
-        target = e.composedPath()[0] ?? e.target;
-        timer = setTimeout(fire, LONG_PRESS_MS);
-    };
-
-    const onPointerMove = (e: PointerEvent): void => {
-        if (timer === null) return;
-
-        const drifted =
-            Math.abs(e.clientX - originX) > MOVE_TOLERANCE_PX ||
-            Math.abs(e.clientY - originY) > MOVE_TOLERANCE_PX;
-
-        if (drifted) cancel();
-    };
-
-    const onContextMenu = (e: Event): void => {
-        // Ours. Everything below is about somebody else's.
-        if (ours.has(e)) return;
-
-        if (timer !== null) {
-            // The browser got there first, so stand down rather than
-            // opening the same menu twice.
-            nativeSeen = true;
-            cancel();
-
-            return;
-        }
-
-        if (justFired) {
-            justFired = false;
-            e.preventDefault();
-            e.stopImmediatePropagation();
-        }
-    };
-
-    const onClick = (e: Event): void => {
-        if (!swallowClick) return;
-
-        swallowClick = false;
-        e.preventDefault();
-        e.stopImmediatePropagation();
-    };
-
-    // Capture throughout: a component handler that stops propagation
-    // (every context-menu handler in the app does) must not be able to
-    // hide the gesture from this, and the suppressors have to run
-    // before anything that would act on the event.
-    const opts = { capture: true } as const;
-
-    document.addEventListener('pointerdown', onPointerDown, opts);
-    document.addEventListener('pointermove', onPointerMove, opts);
-    document.addEventListener('pointerup', cancel, opts);
-    document.addEventListener('pointercancel', cancel, opts);
-    document.addEventListener('contextmenu', onContextMenu, opts);
-    document.addEventListener('click', onClick, opts);
-    // A scroll started by something other than the finger (momentum, a
-    // programmatic reveal) still means the press was not a press.
-    document.addEventListener('scroll', cancel, { capture: true, passive: true });
-
-    uninstall = () => {
-        cancel();
-        document.removeEventListener('pointerdown', onPointerDown, opts);
-        document.removeEventListener('pointermove', onPointerMove, opts);
-        document.removeEventListener('pointerup', cancel, opts);
-        document.removeEventListener('pointercancel', cancel, opts);
-        document.removeEventListener('contextmenu', onContextMenu, opts);
-        document.removeEventListener('click', onClick, opts);
-        document.removeEventListener('scroll', cancel, opts);
-        uninstall = null;
-    };
-
-    return uninstall;
-}

frontend/src/utils/selection-controller.ts

@@ -19,6 +19,29 @@ export class SelectionController implements ReactiveController {
     private host: SelectionHost;
     private _selectedItems: Set<string> = new Set();
     private lastSelectedIndex: number | null = null;
+    private _mode = false;
+
+    /**
+     * Whether the list is in *selection mode* (plan 019, #63).
+     *
+     * A finger has no modifier keys, so the ctrl/shift semantics this
+     * controller was written for cannot be expressed by touch at all.
+     * Selection mode is the platform's answer: a long press enters it,
+     * and while it is on, a tap toggles a row instead of playing it.
+     *
+     * It is a flag *here* rather than a fifth concept beside the
+     * controller because all four surfaces that select
+     * (`track-list`, `queue-panel` and both playlist detail views)
+     * already share this class -- so "is this list selecting" has one
+     * answer per list, in the object that already owns the selection
+     * it would otherwise contradict.
+     *
+     * A mouse never sets it. Desktop selection is unchanged and stays
+     * modeless, which is what `handleItemClick` still implements.
+     */
+    get selectionMode(): boolean {
+        return this._mode;
+    }
 
     constructor(host: SelectionHost) {
         this.host = host;
@@ -136,8 +159,64 @@ export class SelectionController implements ReactiveController {
         return true;
     }
 
+    /**
+     * Enter selection mode with `key` selected.
+     *
+     * The row the gesture was made on is selected, rather than the
+     * mode opening empty: a long press is a statement about *that*
+     * row, and an action bar with nothing in it is a mode the user has
+     * to make a second gesture to escape.
+     */
+    enterSelectionMode(key: string, index: number): void {
+        this._mode = true;
+        this._selectedItems = new Set([key]);
+        this.lastSelectedIndex = index;
+        this.host.requestUpdate();
+        this.host.onSelectionChanged?.();
+    }
+
+    /**
+     * Toggle one row, and leave the mode when the last one goes.
+     *
+     * Deselecting everything is how Android's own list surfaces exit
+     * selection mode, and it matters more here than convention: the
+     * mode changes what a tap *means*, so a mode with an empty
+     * selection is a list where tapping does nothing and nothing on
+     * screen says why.
+     */
+    toggleInMode(key: string, index: number): void {
+        const next = new Set(this._selectedItems);
+
+        if (next.has(key)) next.delete(key);
+        else next.add(key);
+
+        this._selectedItems = next;
+        this.lastSelectedIndex = index;
+
+        if (next.size === 0) this._mode = false;
+
+        this.host.requestUpdate();
+        this.host.onSelectionChanged?.();
+    }
+
+    /** Leave selection mode, dropping the selection with it. */
+    exitSelectionMode(): void {
+        if (!this._mode && this._selectedItems.size === 0) return;
+
+        this._mode = false;
+        this._selectedItems = new Set();
+        this.lastSelectedIndex = null;
+        this.host.requestUpdate();
+        this.host.onSelectionChanged?.();
+    }
+
     /** Clear the entire selection. */
     clear(): void {
+        // The mode goes with it: every caller of this means "the
+        // selection is no longer meaningful", and a mode outliving the
+        // selection it was showing is the empty-mode trap above.
+        this._mode = false;
+
         if (this._selectedItems.size === 0) return;
 
         this._selectedItems = new Set();
@@ -176,6 +255,13 @@ export class SelectionController implements ReactiveController {
         if (next.size === this._selectedItems.size) return;
 
         this._selectedItems = next;
+
+        // A refetch that emptied the selection also ends the mode --
+        // otherwise removing the last selected track from the library
+        // leaves the list in a state where a tap selects and the bar
+        // is gone.
+        if (next.size === 0) this._mode = false;
+
         this.host.requestUpdate();
         this.host.onSelectionChanged?.();
     }

frontend/src/utils/swipe-to-queue.ts

@@ -0,0 +1,362 @@
+import { css, html, nothing } from 'lit';
+import type { ReactiveController, ReactiveControllerHost } from 'lit';
+import { classMap } from 'lit/directives/class-map.js';
+
+import { queueStore } from '@store/queue-store';
+import { ICON_QUEUE } from '@utils/icon-language';
+import type { SwipeEvent } from '@utils/touch-gestures';
+
+/**
+ * Swipe a row right to add it to the queue (plan 019, #63).
+ *
+ * This is the *affordance* and the arithmetic, written once, because
+ * three lists want it: `track-list` and both playlist detail views.
+ * It was `track-list`'s own for one phase and is here rather than
+ * copied twice, on the rule the rest of this app is built on — three
+ * copies of "how far is far enough" is three chances for them to
+ * disagree, which is what `utils/library-status.ts` and
+ * `utils/ownership.ts` each exist to have stopped happening.
+ *
+ * The host keeps three things: what a row *is*, what a swipe on it
+ * would queue, and what to call it afterwards. Everything else —
+ * the threshold, the reveal, the settle, the announcement, the
+ * repaint — is here.
+ *
+ * **The queue panel deliberately does not use it.** A right swipe means
+ * *add to the queue* everywhere it exists, and a queue row is already
+ * in the queue; the only thing it could sensibly mean there is
+ * *remove*, which is the same gesture with the opposite effect one
+ * screen away. Removing a queue row is on its own row (the ×), on its
+ * bottom sheet since #60, and on the selection bar #63 gave it.
+ *
+ * Five things about it are load-bearing.
+ *
+ * **Both halves of the device fix are here or next door.**
+ * `swipeRevealStyles` carries `touch-action: pan-y` on `[data-swipe]`,
+ * and `utils/touch-gestures.ts` carries the non-passive
+ * `preventDefault`. Chrome 113's WebView cancels the pointer stream
+ * ~16px into any drag whatever `touch-action` says, and with the
+ * `preventDefault` alone but `touch-action` at `auto` the gesture dies
+ * after one move. Neither works without the other and **both are
+ * correct in Chromium either way**, which is why the component tier
+ * asserts the stylesheet rather than the rendering.
+ *
+ * **The row does not move; its cells do.** A row here is
+ * `contain: strict` with `overflow: hidden`, so translating the row
+ * and counter-translating a pane inside it puts that pane at a
+ * negative offset inside a clipping box, where it is simply not
+ * painted. Sliding the children instead leaves the pane where it was
+ * drawn, clips the cells off the right edge, and needs no wrapper
+ * element in a row that is already a grid.
+ *
+ * **The travel is written to the row's own style, never rendered.**
+ * One render when the gesture starts, one when it crosses the
+ * threshold, one when it ends — a virtualizer re-rendering every
+ * visible row per frame of one finger's travel is exactly what audit
+ * `perf.m1` is about.
+ *
+ * **The threshold is a fraction of the row**, with a floor. The row is
+ * 424x52 on the reference device, so a threshold in bare pixels is a
+ * fraction of a row height on one screen and a third of the width on
+ * the next.
+ *
+ * **It is not only a colour** (WCAG 1.4.1, the rule the playing-row
+ * marker exists for). The pane carries the queue icon and words, the
+ * words change at the threshold, and the outcome goes to a live
+ * region — one glyph throughout, because a tick is `ICON_IN_LIBRARY`
+ * and means *you own this*.
+ */
+
+/** How far along the row a swipe has to reach to mean it. */
+export const SWIPE_COMMIT_FRACTION = 0.3;
+
+/** … and a floor, for a narrow list embedded in a detail page. */
+export const SWIPE_COMMIT_MIN_PX = 72;
+
+/** How long the reveal holds its confirmation before snapping back. */
+const CONFIRM_MS = 550;
+
+/** The snap itself. `swipeRevealStyles` states the same number. */
+const SETTLE_MS = 180;
+
+/** What a swipe on one row would do, as the host understands it. */
+export interface SwipeTarget {
+    /** Which row draws the reveal. */
+    index: number;
+
+    /** The file paths a commit queues, in the order they are shown. */
+    filePaths: string[];
+
+    /** What to call a single track when saying it was added. */
+    label: string;
+}
+
+export interface SwipeToQueueOptions {
+    /**
+     * The row the gesture is on, or null for anything that is not a
+     * swipeable row — a header, a gap, a track with no file.
+     */
+    resolve(e: SwipeEvent): SwipeTarget | null;
+
+    /**
+     * Repaint the rows. A `<lit-virtualizer>` renders through the
+     * `virtualize` directive and reacts to its *own* properties, so a
+     * host update alone leaves the rows exactly as they were.
+     */
+    repaint(): void;
+}
+
+export class SwipeToQueue implements ReactiveController {
+    private host: ReactiveControllerHost;
+    private opts: SwipeToQueueOptions;
+
+    /** Which row is being swiped, and therefore draws a reveal. */
+    private index: number | null = null;
+
+    /** Past the commit threshold: the reveal says so, in words. */
+    private armed = false;
+
+    /** Committed, and holding its confirmation. */
+    private done = false;
+
+    private row: HTMLElement | null = null;
+    private keys: string[] = [];
+    private commitPx = 0;
+    private settleTimer = 0;
+
+    /** What the gesture did, for anyone not watching the row. */
+    announcement = '';
+
+    constructor(host: ReactiveControllerHost, opts: SwipeToQueueOptions) {
+        this.host = host;
+        this.opts = opts;
+        host.addController(this);
+    }
+
+    hostConnected(): void {
+        // No-op; state is component-local.
+    }
+
+    hostDisconnected(): void {
+        window.clearTimeout(this.settleTimer);
+        this.forget();
+    }
+
+    /** Whether this row is the one under the finger. */
+    isSwiping(index: number): boolean {
+        return this.index === index;
+    }
+
+    onSwipeStart = (e: SwipeEvent): void => {
+        // Rightward only. Nothing is bound to a leftward swipe, and
+        // claiming one would take a gesture away to do nothing with it.
+        if (e.detail.dx <= 0) return;
+
+        const target = this.opts.resolve(e);
+
+        if (!target || target.filePaths.length === 0) return;
+
+        const row = (e.target as HTMLElement).closest(
+            '[data-swipe]',
+        ) as HTMLElement | null;
+
+        if (!row) return;
+
+        e.preventDefault();
+
+        this.row = row;
+        this.keys = target.filePaths;
+        this.trackLabel = target.label;
+        this.commitPx = Math.max(
+            SWIPE_COMMIT_MIN_PX,
+            row.getBoundingClientRect().width * SWIPE_COMMIT_FRACTION,
+        );
+        this.armed = false;
+        this.done = false;
+        this.index = target.index;
+        this.host.requestUpdate();
+        this.opts.repaint();
+        this.offset(0);
+    };
+
+    onSwipeMove = (e: SwipeEvent): void => {
+        if (this.index === null) return;
+
+        const dx = Math.min(Math.max(e.detail.dx, 0), this.commitPx * 2);
+        const armed = dx >= this.commitPx;
+
+        if (armed !== this.armed) {
+            this.armed = armed;
+            this.host.requestUpdate();
+            this.opts.repaint();
+        }
+
+        this.offset(dx);
+    };
+
+    onSwipeEnd = (e: SwipeEvent): void => {
+        if (this.index === null) return;
+
+        if (e.detail.canceled || e.detail.dx < this.commitPx) {
+            this.settle(0);
+
+            return;
+        }
+
+        queueStore.addTracksToQueue(this.keys);
+
+        const count = this.keys.length;
+
+        // The reveal is the only thing on screen that says this
+        // happened -- the queue panel may well be closed -- so it holds
+        // its confirmation for a moment rather than vanishing the
+        // instant the finger lifts.
+        this.done = true;
+        this.announcement =
+            count === 1
+                ? `Added ${this.label()} to the queue.`
+                : `Added ${count} tracks to the queue.`;
+        this.host.requestUpdate();
+        this.opts.repaint();
+        this.settle(CONFIRM_MS);
+    };
+
+    /** What is revealed behind the row, in three states. */
+    renderReveal(index: number) {
+        if (this.index !== index) return nothing;
+
+        const count = this.keys.length;
+        const what = count === 1 ? 'to queue' : `${count} tracks to queue`;
+        const words = this.done
+            ? 'Added'
+            : this.armed
+                ? 'Release to add'
+                : `Add ${what}`;
+
+        return html`
+            <div
+                class=${classMap({ 'swipe-reveal': true, armed: this.armed })}
+                aria-hidden="true"
+                data-testid="swipe-reveal"
+            >
+                <wa-icon name=${ICON_QUEUE}></wa-icon>
+                <span>${words}</span>
+            </div>
+        `;
+    }
+
+    /**
+     * What to call a single track, taken when the gesture starts.
+     *
+     * Held rather than looked up at the end, because a swipe outlives
+     * a refetch: the store replaces its array when a play count
+     * changes, which is once a song.
+     */
+    private trackLabel = '';
+
+    private label(): string {
+        return this.trackLabel === '' ? 'the track' : this.trackLabel;
+    }
+
+    /** Write the travel to the row itself, with no render. */
+    private offset(dx: number): void {
+        this.row?.style.setProperty('--yj-swipe-dx', `${dx}px`);
+    }
+
+    /**
+     * Put the row back, after `delay`, and forget the swipe.
+     *
+     * The row element is held rather than looked up again: a
+     * virtualizer recycles its rows, and by the time this runs the
+     * element may be drawing a different track. Clearing the property
+     * off whatever it holds now is right either way, since `index` is
+     * what decides who draws the reveal.
+     */
+    private settle(delay: number): void {
+        const row = this.row;
+
+        window.clearTimeout(this.settleTimer);
+
+        this.settleTimer = window.setTimeout(() => {
+            row?.classList.add('settling');
+            this.offset(0);
+
+            this.settleTimer = window.setTimeout(() => {
+                row?.classList.remove('settling');
+                row?.style.removeProperty('--yj-swipe-dx');
+                this.forget();
+                this.host.requestUpdate();
+                this.opts.repaint();
+            }, SETTLE_MS);
+        }, delay);
+    }
+
+    private forget(): void {
+        this.row = null;
+        this.index = null;
+        this.armed = false;
+        this.done = false;
+    }
+}
+
+/**
+ * The reveal, and the `touch-action` half of what makes the gesture
+ * reach us on the device.
+ *
+ * Keyed on `[data-swipe]` rather than on a class name, so one
+ * stylesheet serves three lists whose rows are called three different
+ * things.
+ */
+export const swipeRevealStyles = css`
+    /* Half of what makes the gesture reach us on Chrome 113's WebView:
+       auto lets it commit to a horizontal pan on the first move past
+       slop, and the pointer stream is cancelled before any threshold
+       can be crossed. The other half is the non-passive preventDefault
+       in utils/touch-gestures.ts, and neither works alone -- both were
+       measured three ways on the phone. Never none: that takes the
+       list's own vertical scrolling with it. */
+    [data-swipe] {
+        touch-action: pan-y;
+    }
+
+    .swipe-reveal {
+        position: absolute;
+        left: 0;
+        top: 0;
+        bottom: 0;
+        width: var(--yj-swipe-dx, 0px);
+        box-sizing: border-box;
+        display: flex;
+        align-items: center;
+        gap: 0.4em;
+        padding-left: 8px;
+        overflow: hidden;
+        white-space: nowrap;
+        pointer-events: none;
+        font-size: var(--yj-text-xs);
+        background-color: var(--yj-bg-elevated, #343a40);
+        color: var(--yj-text-secondary, #b3b3b3);
+    }
+
+    .swipe-reveal.armed {
+        background-color: var(--yj-success, #2f9e44);
+        color: var(--yj-success-fg, #fff);
+    }
+
+    /* The children move, not the row -- see the header. */
+    [data-swipe].swiping > :not(.swipe-reveal) {
+        transform: translateX(var(--yj-swipe-dx, 0px));
+    }
+
+    [data-swipe].settling > * {
+        transition:
+            transform 160ms ease-out,
+            width 160ms ease-out;
+    }
+
+    @media (prefers-reduced-motion: reduce) {
+        [data-swipe].settling > * {
+            transition: none;
+        }
+    }
+`;

frontend/src/utils/touch-gestures.ts

@@ -0,0 +1,619 @@
+/**
+ * The touch gestures, as one document listener (plan 019, #63).
+ *
+ * This replaces `utils/long-press.ts` rather than sitting beside it,
+ * and that is the point: two document listeners both claiming the
+ * 500ms hold is exactly the fault that file's own header warns about.
+ * What it did — one capture listener, the target from
+ * `composedPath()[0]`, the browser's own gesture winning, the trailing
+ * click swallowed — is kept whole. What changes is what the gesture
+ * *means*.
+ *
+ * **A gesture is announced, not acted on.** Two composed, cancelable
+ * events are dispatched on the element the finger actually landed on:
+ *
+ *   `yj-tap`         a short press that did not drift
+ *   `yj-long-press`  a press that held still for LONG_PRESS_MS
+ *   `yj-swipe-start` a press that has travelled decisively sideways
+ *
+ * A claimed swipe is then followed by `yj-swipe-move` and one
+ * `yj-swipe-end`, which is guaranteed: a swipe that the browser or a
+ * second finger takes away still ends, with `canceled` set, so the
+ * affordance a component put on screen always has something to snap
+ * back from.
+ *
+ * A component that wants the gesture handles it and calls
+ * `preventDefault()`. Nothing else changes. That shape is what lets
+ * this reassign the hold without touching a single one of the fourteen
+ * context menus downstream of it: **an unclaimed `yj-long-press` still
+ * becomes a synthetic `contextmenu`**, so a card grid, an Explore
+ * result or a playlist row behaves exactly as it did, and only the
+ * lists that opt in get selection mode.
+ *
+ * The same rule keeps taps honest. An unclaimed `yj-tap` does nothing
+ * at all and the browser's click follows normally, so every button,
+ * link and checkbox in the app is untouched by this file. Only a
+ * claimed tap has its click swallowed — otherwise playing a track
+ * would also select it.
+ *
+ * Five things are load-bearing.
+ *
+ * **The predicate is the pointer, not the platform** (plan 019,
+ * decision 1). `pointerType === 'touch'`, per event — so an Android
+ * tablet over 600px, a touchscreen laptop with a mouse also plugged
+ * in, and a narrow desktop window are all right for free, and there is
+ * no second declaration of what a phone does. Keyed on a viewport
+ * width, the first of those three gets desktop semantics on a
+ * touchscreen, which is the inversion #63 exists to fix, on the
+ * platform it exists for.
+ *
+ * **There is no double-tap**, and it is not an omission — see plan
+ * 019, decision 2. Measured on the reference device, the play command
+ * to `TrackChanged` is ~100ms; a double-tap discriminator has to hold
+ * every tap for the app's own `DOUBLE_CLICK_GRACE_MS` of 250 before it
+ * can act, which is 3.5x the primary interaction in the app to reach a
+ * menu that long-press already reaches.
+ *
+ * **The target comes from `composedPath()[0]`**, not
+ * `elementFromPoint`, which stops at the outermost shadow host: every
+ * list in this app delegates inside one, so an event dispatched on the
+ * host reaches a delegated listener and no per-row one.
+ *
+ * **A browser that fires its own `contextmenu` is a trigger, not a
+ * competitor**, and that is a change from `long-press.ts` rather than
+ * an inherited rule. It used to stand down when a trusted
+ * `contextmenu` arrived, because both paths ended in the same place: a
+ * context menu. They no longer do — ours may end in selection mode —
+ * so standing down means the gesture silently does the *old* thing.
+ *
+ * Measured on the reference device, which is the only tier that can
+ * see this: Chrome 113's WebView fires its own `contextmenu` on a long
+ * press, so a hold on a track row opened the context menu and
+ * `yj-long-press` was never announced at all. Every test in the
+ * component tier passed, because dispatched pointer events do not make
+ * a browser synthesise one.
+ *
+ * So a trusted `contextmenu` arriving mid-press *becomes* the long
+ * press: `yj-long-press` is announced from it, and only if a component
+ * claims it is the native event suppressed. Unclaimed, it propagates
+ * untouched and opens the menu it always did — which is the same
+ * "browser wins" outcome, now reached by asking rather than assuming.
+ *
+ * Ours and the browser's are still told apart by identity rather than
+ * `isTrusted` — a `WeakSet` of the events this module made — so the
+ * suppressor cannot eat the event it exists to deliver, and a test can
+ * stand in for a browser that fires one.
+ *
+ * **The click swallow is keyed on the gesture**, cleared by the next
+ * `pointerdown` rather than by a time window, so the first tap on a
+ * sheet that just opened is not eaten too.
+ *
+ * ## The swipe runs on touch events, and that is not a style choice
+ *
+ * Everything above is Pointer Events. The swipe is not, and the reason
+ * is measured on the reference device rather than reasoned about:
+ * **Chrome 113's Android WebView cancels the pointer stream ~16px into
+ * any drag, whatever `touch-action` says.** Three values were tried on
+ * a track row, driving a real finger with `adb shell input swipe`:
+ *
+ * ```
+ * touch-action: auto   pointerdown, 1 move,  pointercancel
+ * touch-action: pan-y  pointerdown, 2 moves, pointercancel
+ * touch-action: none   pointerdown, 2 moves, pointercancel
+ * ```
+ *
+ * `touchmove` kept firing throughout all three. So a swipe recognised
+ * from `pointermove` is a swipe that dies 16px in — plan 019 predicted
+ * the class of failure ("works in Chromium and not on the phone") and
+ * named `touch-action: pan-y` as the fix; it is half of it.
+ *
+ * The other half is that **a non-passive `touchmove` that calls
+ * `preventDefault()` is what keeps the gesture ours**. With it, the
+ * same swipe ran to 12 moves and a `pointerup` at full travel.
+ *
+ * Both halves are required, and that was measured too: with the
+ * `preventDefault` in place but `touch-action` back at `auto`, the
+ * gesture died after **one** move. The reading is that `auto` lets the
+ * browser commit to a horizontal pan on the first move past slop —
+ * before any threshold of ours can have been crossed — while `pan-y`
+ * leaves it undecided long enough for the second move to claim it.
+ *
+ * So a surface that wants a horizontal swipe declares
+ * `touch-action: pan-y` (`track-list`'s `.track-row` does) *and* gets
+ * this module's `preventDefault`. Neither alone works on the device,
+ * and **both work in Chromium either way**, which is exactly why this
+ * paragraph exists rather than a test.
+ *
+ * `touch-action: none` is the one value to avoid: it also takes the
+ * list's vertical scrolling away, which was measured as a list that
+ * would not move.
+ *
+ * Two consequences of the touch listener worth knowing.
+ *
+ * **It is non-passive, which costs the compositor's scroll fast path**
+ * for the first touchmoves of every scroll, until the browser starts
+ * scrolling and stops waiting on us. That is the standard price of a
+ * horizontal gesture in a scroller and it is paid once per gesture,
+ * not per frame; a vertical drag on the device still scrolls the
+ * virtualizer 81px on the same measurement that the horizontal one
+ * survives.
+ *
+ * **The tie breaks toward scrolling**, deliberately and in that order:
+ * vertical drift past the tolerance vetoes the swipe outright, and a
+ * gesture that is not *strictly* more horizontal than vertical is the
+ * scroller's. A list that will not scroll is unusable; a swipe that
+ * needs a second try is not.
+ */
+
+/** How long a press must hold still to mean "long press". */
+export const LONG_PRESS_MS = 500;
+
+/**
+ * How far a press may drift and still count. Below a finger's own
+ * jitter is a gesture nobody can perform; above ~12px it starts
+ * stealing the first frames of a scroll.
+ */
+export const MOVE_TOLERANCE_PX = 10;
+
+/**
+ * How far a press must travel sideways before it is a swipe.
+ *
+ * It has a ceiling the other constants do not: the browser's own
+ * decision is made a little past this, so a threshold much higher is a
+ * gesture the device never delivers. Measured, the second `touchmove`
+ * of an `adb input swipe` lands at ~19px and the pointer stream dies
+ * just after it, so 12 is inside that window with room for a slower
+ * finger.
+ */
+export const SWIPE_START_PX = 12;
+
+/** Detail carried by both gesture events. */
+export interface GestureDetail {
+    /** Where the finger was, in client coordinates — a menu opens here. */
+    x: number;
+    y: number;
+}
+
+/** Detail carried by the three swipe events. */
+export interface SwipeDetail {
+    /** Travel from where the finger landed. Signed: right is positive. */
+    dx: number;
+    dy: number;
+    /**
+     * The gesture was taken away rather than finished — a second
+     * finger, a `touchcancel`, a scroll underneath. Only ever true on
+     * `yj-swipe-end`, and it is the difference between "do the thing"
+     * and "put the row back".
+     */
+    canceled: boolean;
+}
+
+export type GestureEvent = CustomEvent<GestureDetail>;
+export type SwipeEvent = CustomEvent<SwipeDetail>;
+
+declare global {
+    interface HTMLElementEventMap {
+        'yj-tap': GestureEvent;
+        'yj-long-press': GestureEvent;
+        'yj-swipe-start': SwipeEvent;
+        'yj-swipe-move': SwipeEvent;
+        'yj-swipe-end': SwipeEvent;
+    }
+}
+
+/** The active installation, so a second call is a no-op rather than a
+ *  second listener set. */
+let uninstall: (() => void) | null = null;
+
+/** The events this module dispatched. Identity, not `isTrusted`. */
+const ours = new WeakSet<Event>();
+
+/**
+ * Install the gestures. Idempotent; returns the uninstaller (which the
+ * tests use — the app installs once and never removes it).
+ */
+export function installTouchGestures(): () => void {
+    if (uninstall) return uninstall;
+
+    let timer: ReturnType<typeof setTimeout> | null = null;
+    let originX = 0;
+    let originY = 0;
+    let target: EventTarget | null = null;
+
+    /** The press is still a candidate for a tap: it has neither
+     *  drifted nor become a long press. */
+    let tapCandidate = false;
+
+    /** A trusted `contextmenu` arrived for this press: the browser has
+     *  it covered. */
+    let nativeSeen = false;
+
+    /** A gesture was claimed, and the click ending it is not a click on
+     *  anything. */
+    let swallowClick = false;
+
+    /**
+     * This press has already produced its outcome, so a trusted
+     * `contextmenu` arriving now is a duplicate of it.
+     *
+     * It covers **both** outcomes, and that is a fix rather than a
+     * tidy-up. `nativeSeen` handles the browser's menu arriving
+     * *during* the hold; the reverse order was never handled, and it
+     * happens: measured on the reference device over four holds, two
+     * of them fired our 500ms timer and then delivered a trusted
+     * `contextmenu` 50-70ms later, which nothing suppressed — so the
+     * context menu opened on top of the selection bar, intermittently,
+     * on exactly the surface #63 exists to have changed. Neither the
+     * component tier nor the e2e tier can see it: no browser they run
+     * in synthesises a `contextmenu` from a dispatched press at all.
+     */
+    let justFired = false;
+
+    // --- the swipe, which runs on touch events; see the header ------
+
+    /** Where the finger landed, and what it landed on. */
+    let swipeTarget: EventTarget | null = null;
+    let swipeOriginX = 0;
+    let swipeOriginY = 0;
+
+    /** The last travel, kept so a `touchcancel` — which carries no
+     *  coordinates for a touch that is already gone — can still say how
+     *  far the row had moved. */
+    let lastDx = 0;
+    let lastDy = 0;
+
+    /** A component claimed the swipe: it is ours until the finger
+     *  lifts, and every `touchmove` is prevented. */
+    let swiping = false;
+
+    /** This press can no longer become a swipe — it went vertical, a
+     *  second finger arrived, or nobody claimed it. */
+    let swipeVetoed = false;
+
+    const cancel = (): void => {
+        if (timer !== null) clearTimeout(timer);
+
+        timer = null;
+        target = null;
+        tapCandidate = false;
+    };
+
+    /**
+     * Announce a gesture on the element the finger landed on.
+     * Returns whether a component claimed it.
+     */
+    const announce = (name: 'yj-tap' | 'yj-long-press', el: EventTarget): boolean => {
+        const event: GestureEvent = new CustomEvent<GestureDetail>(name, {
+            bubbles: true,
+            cancelable: true,
+            // Or it stops at the shadow root the row lives in, and the
+            // delegated listeners never see it.
+            composed: true,
+            detail: { x: originX, y: originY },
+        });
+
+        ours.add(event);
+        el.dispatchEvent(event);
+
+        return event.defaultPrevented;
+    };
+
+    const fireContextMenu = (el: EventTarget): void => {
+        justFired = true;
+
+        const menu = new MouseEvent('contextmenu', {
+            bubbles: true,
+            cancelable: true,
+            composed: true,
+            clientX: originX,
+            clientY: originY,
+            button: 2,
+        });
+
+        ours.add(menu);
+        el.dispatchEvent(menu);
+    };
+
+    const onLongPress = (): void => {
+        timer = null;
+        tapCandidate = false;
+
+        const el = target;
+
+        target = null;
+
+        if (nativeSeen || !el) return;
+
+        // The gesture happened either way, so the click that ends it is
+        // never a click on anything -- whether a list claimed it for
+        // selection mode or a card grid let it fall through to a menu.
+        swallowClick = true;
+
+        // The press is answered, so a trusted `contextmenu` for it is
+        // late rather than new. `fireContextMenu` sets this too; it is
+        // set here as well so the *claimed* branch is covered, which
+        // is the branch that was showing a menu over the bar.
+        justFired = true;
+
+        // An unclaimed long press is what it has always been. This is
+        // the whole reason the fourteen context menus need no change.
+        if (!announce('yj-long-press', el)) fireContextMenu(el);
+    };
+
+    const onPointerDown = (e: PointerEvent): void => {
+        // A new gesture: whatever the last one left behind is stale.
+        swallowClick = false;
+        justFired = false;
+        nativeSeen = false;
+        cancel();
+
+        if (e.pointerType !== 'touch' || !e.isPrimary) return;
+
+        originX = e.clientX;
+        originY = e.clientY;
+        target = e.composedPath()[0] ?? e.target;
+        tapCandidate = true;
+        timer = setTimeout(onLongPress, LONG_PRESS_MS);
+    };
+
+    /**
+     * Announce a swipe on the element the finger landed on.
+     * Returns whether a component claimed it (only `start` asks).
+     */
+    const announceSwipe = (
+        name: 'yj-swipe-start' | 'yj-swipe-move' | 'yj-swipe-end',
+        el: EventTarget,
+        canceled = false,
+    ): boolean => {
+        const event: SwipeEvent = new CustomEvent<SwipeDetail>(name, {
+            bubbles: true,
+            cancelable: name === 'yj-swipe-start',
+            composed: true,
+            detail: { dx: lastDx, dy: lastDy, canceled },
+        });
+
+        ours.add(event);
+        el.dispatchEvent(event);
+
+        return event.defaultPrevented;
+    };
+
+    /**
+     * End a claimed swipe, once.
+     *
+     * Every exit from a swipe comes through here so that `yj-swipe-end`
+     * is guaranteed: a component that has put a reveal on screen and a
+     * row half off its own left edge has no other way to learn the
+     * gesture is over.
+     */
+    const endSwipe = (canceled: boolean): void => {
+        const el = swipeTarget;
+
+        swipeTarget = null;
+
+        if (!swiping) return;
+
+        swiping = false;
+
+        if (!el) return;
+
+        // The gesture happened, so the click that ends it is not a
+        // click on the row it ended over.
+        swallowClick = true;
+        announceSwipe('yj-swipe-end', el, canceled);
+    };
+
+    const onTouchStart = (e: TouchEvent): void => {
+        endSwipe(true);
+
+        lastDx = 0;
+        lastDy = 0;
+
+        // A second finger is a pinch or a scroll, never one of ours.
+        swipeVetoed = e.touches.length !== 1;
+
+        if (swipeVetoed) return;
+
+        const touch = e.touches[0];
+
+        if (!touch) return;
+
+        swipeOriginX = touch.clientX;
+        swipeOriginY = touch.clientY;
+        // `composedPath()[0]` for the reason the press path uses it: a
+        // list delegates inside its own shadow root.
+        swipeTarget = e.composedPath()[0] ?? e.target;
+    };
+
+    const onTouchMove = (e: TouchEvent): void => {
+        if (swipeVetoed || !swipeTarget) return;
+
+        if (e.touches.length !== 1) {
+            endSwipe(true);
+            swipeVetoed = true;
+
+            return;
+        }
+
+        const touch = e.touches[0];
+
+        if (!touch) return;
+
+        lastDx = touch.clientX - swipeOriginX;
+        lastDy = touch.clientY - swipeOriginY;
+
+        if (swiping) {
+            // This is what keeps the stream alive on the device. It is
+            // only ever reached for a *claimed* swipe, so nothing that
+            // scrolls is ever prevented.
+            e.preventDefault();
+            announceSwipe('yj-swipe-move', swipeTarget);
+
+            return;
+        }
+
+        // Vertical first: past the tolerance the list has it, and a
+        // gesture that is exactly diagonal is the list's too.
+        if (
+            Math.abs(lastDy) > MOVE_TOLERANCE_PX &&
+            Math.abs(lastDy) >= Math.abs(lastDx)
+        ) {
+            swipeVetoed = true;
+            swipeTarget = null;
+
+            return;
+        }
+
+        if (
+            Math.abs(lastDx) < SWIPE_START_PX ||
+            Math.abs(lastDx) <= Math.abs(lastDy)
+        ) {
+            return;
+        }
+
+        if (!announceSwipe('yj-swipe-start', swipeTarget)) {
+            // Nobody wants it. Leave the gesture to the browser rather
+            // than holding it open for the rest of the press.
+            swipeVetoed = true;
+            swipeTarget = null;
+
+            return;
+        }
+
+        swiping = true;
+
+        // It is not a tap and it is not a hold.
+        cancel();
+        e.preventDefault();
+    };
+
+    const onTouchEnd = (): void => {
+        endSwipe(false);
+    };
+
+    const onTouchCancel = (): void => {
+        endSwipe(true);
+    };
+
+    const onPointerMove = (e: PointerEvent): void => {
+        if (timer === null) return;
+
+        const drifted =
+            Math.abs(e.clientX - originX) > MOVE_TOLERANCE_PX ||
+            Math.abs(e.clientY - originY) > MOVE_TOLERANCE_PX;
+
+        // A drifted press is neither gesture -- it is a scroll, and the
+        // virtualizer's, not ours.
+        if (drifted) cancel();
+    };
+
+    const onPointerUp = (): void => {
+        const el = target;
+        const wasTap = tapCandidate && timer !== null;
+
+        // Clears the long-press timer, so a tap cannot also become one.
+        cancel();
+
+        if (!wasTap || !el) return;
+
+        // Only a *claimed* tap swallows its click. An unclaimed one has
+        // to fall through untouched, or every button in the app stops
+        // working.
+        if (announce('yj-tap', el)) swallowClick = true;
+    };
+
+    const onContextMenu = (e: Event): void => {
+        // Ours. Everything below is about somebody else's.
+        if (ours.has(e)) return;
+
+        if (timer !== null) {
+            // The browser recognised the same hold this was timing.
+            // Use its event as the trigger rather than racing it --
+            // and rather than standing down, which is what the old
+            // rule did and which now silently means "do the thing this
+            // gesture used to do".
+            const el = e.composedPath()[0] ?? e.target;
+
+            nativeSeen = true;
+            cancel();
+
+            if (!el) return;
+
+            swallowClick = true;
+
+            // Claimed: the component wants selection mode, so the
+            // browser's menu must not also open. Unclaimed: let it
+            // through exactly as before.
+            if (announce('yj-long-press', el)) {
+                e.preventDefault();
+                e.stopImmediatePropagation();
+            }
+
+            return;
+        }
+
+        if (justFired) {
+            justFired = false;
+            e.preventDefault();
+            e.stopImmediatePropagation();
+        }
+    };
+
+    const onClick = (e: Event): void => {
+        if (!swallowClick) return;
+
+        swallowClick = false;
+        e.preventDefault();
+        e.stopImmediatePropagation();
+    };
+
+    // Capture throughout: a component handler that stops propagation
+    // (every context-menu handler in the app does) must not be able to
+    // hide the gesture from this, and the suppressors have to run
+    // before anything that would act on the event.
+    const opts = { capture: true } as const;
+
+    // Non-passive, because `onTouchMove` has to be able to prevent the
+    // default for a claimed swipe -- see the header. The other three
+    // are passive: they only read.
+    const blocking = { capture: true, passive: false } as const;
+    const listening = { capture: true, passive: true } as const;
+
+    /** A surface moved under the finger: neither gesture survives it. */
+    const abort = (): void => {
+        endSwipe(true);
+        cancel();
+    };
+
+    document.addEventListener('pointerdown', onPointerDown, opts);
+    document.addEventListener('pointermove', onPointerMove, opts);
+    document.addEventListener('pointerup', onPointerUp, opts);
+    document.addEventListener('pointercancel', cancel, opts);
+    document.addEventListener('contextmenu', onContextMenu, opts);
+    document.addEventListener('click', onClick, opts);
+    document.addEventListener('touchstart', onTouchStart, listening);
+    document.addEventListener('touchmove', onTouchMove, blocking);
+    document.addEventListener('touchend', onTouchEnd, listening);
+    document.addEventListener('touchcancel', onTouchCancel, listening);
+    // A scroll started by something other than the finger (momentum, a
+    // programmatic reveal) still means the press was not a press.
+    document.addEventListener('scroll', abort, listening);
+
+    uninstall = () => {
+        abort();
+        document.removeEventListener('pointerdown', onPointerDown, opts);
+        document.removeEventListener('pointermove', onPointerMove, opts);
+        document.removeEventListener('pointerup', onPointerUp, opts);
+        document.removeEventListener('pointercancel', cancel, opts);
+        document.removeEventListener('contextmenu', onContextMenu, opts);
+        document.removeEventListener('click', onClick, opts);
+        document.removeEventListener('touchstart', onTouchStart, opts);
+        document.removeEventListener('touchmove', onTouchMove, opts);
+        document.removeEventListener('touchend', onTouchEnd, opts);
+        document.removeEventListener('touchcancel', onTouchCancel, opts);
+        document.removeEventListener('scroll', abort, opts);
+        uninstall = null;
+    };
+
+    return uninstall;
+}