WebKit draws the same button 36x24 where Chromium draws 33x21, so the
literal this pinned 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: `min-width` and
`min-height` compute to 0px, the font-size still equals that of a bare
button probed in the same page, and all five boxes are identical --
which is what says the desktop is neither sized context. Checked by
re-introducing the `font-size: inherit` regression, which it catches in
Chromium; the literal form could only be checked by hand.
Ten tests, five of which fail on the build before this. The desktop
guard is meant to pass there -- that is its job, and it is the one that
caught a three-pixel regression nothing else could see.
`openTheQueue` moves to the fixtures, because hiding one button failed
ten tests in four files about the back stack and about layout: every
one of them opened the queue by clicking `#queue-button`, and so was
quietly asserting *which* route exists as well as what the queue does.
The route differs by width now and that is the feature.
Two smaller things. The play button is named for its action, so an
exact 'Play' waits out a fixture track -- 11.1s per test, passing by
luck, and it would have failed outright against LONG_TRACK. And the
"nothing playing" case clears the queue itself rather than trusting the
app not to have played anything: `make e2e` runs one long-lived app
across every spec (#168), which is how a deterministic bug first showed
up as a flake.
logan