This bug is not currently tracked.
We should identify tests outside the browser/components/urlbar directory that will fail when we turn on QuantumBar.
I triggered a full-tests try push as an initial step:
(note: the talos tests are just to check they run, not for performance as yet).
I've gone through the try run, and I think I've found all the failing tests. They are now filed and marked as blocking bug 1514162.
Leaving this open, as we'll want to run this again once we've fixed most/all of those bugs.
Marco, I'm confused as to why some of these test related ones are blocking quantumbar-release rather than quantumbar-nightly. I was expecting that we'd need to fix them before we can turn on the pref on permanently for nightly users. Obviously we don't need them for the pref-flip study, but I thought the quantumbar-nightly bug was for preffing on in nightly.
I assumed our "enable in nightly" idea was "partially enable this for some nightly users".
Maybe we should split into enable-in-nightly and enable-for-some-nightly-users. Consider that things like IME and a11y are necessary for a complete pref flip in nightly, and those were already blocking release.
Another try run with the partially landed/WIP patches I've got for fixing tests:
Fresh try push: https://treeherder.mozilla.org/#/jobs?repo=try&revision=5f2b80275d081d89457c7dc83ee35df9be900f0f
The current bugs for the remaining oranges with QuantumBar on are:
Both of these are in progress and are blocking the release via the quantumbar-tests bug.
Marking as fixed for this iteration - bug 1547210 will manage the next one.