1696438 - With the Proton theme, the spacing between pinned tabs changes when tab bar starts/stops overflowing

Status: VERIFIED FIXED

(Firefox :: Tabbed Browser, defect, P2)

Description

[Markus Stange [:mstange]]

Attachment: screen recording

See the attached video.

Build ID 20210303215027

Steps to reproduce:

1. Have a few pinned tabs in your tab bar.
2. Open enough tabs to fill the tab bar but not enough to cause scrolling.
3. Observe the pinned tabs as you open more tabs and the tab bar starts showing the scroll arrows.

Expected results:
The tab bar should feel stable, pinned tabs should not be affected by scrolling in the rest of the tab bar.

Actual results:
When the regular tabs start requiring scrolling, the spacing between the pinned tabs is reduced.

Comment 1

[Jared Wein [:jaws] (please needinfo? me)]

Is this a dupe of bug 1693605?

Comment 2

[Markus Stange [:mstange]]

Ah, maybe. When I filed bug 1693605 I was more thinking about the hit testing aspects, and not about the visual aspects.

Comment 3

[Jared Wein [:jaws] (please needinfo? me)]

Oh sorry, yes I think this is a unique bug and not a duplicate of bug 1693605. It is reproducible on Mac but not on Windows. I think our measurement here is off, probably at https://searchfox.org/mozilla-central/rev/002023eb262be9db3479142355e1675645d52d52/browser/base/content/tabbrowser-tabs.js#1316-1383

Comment 5

[Dão Gottwald [:dao]]

Attachment: Bug 1696438 - Fix pinned tab positioning. r=jaws

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4b1eb7d5fe2d
Fix pinned tab positioning. r=jaws

Comment 7

[Alexandru Michis [:malexandru]]

Backed out 2 changesets (Bug 1695292, Bug 1696438) for causing xpcshell failures in test_trr_cancel.js
Backout link: https://hg.mozilla.org/integration/autoland/rev/20cda15a5e4a486d289a4fcfc5ab0997789fd48c
Push with failures, failure log.

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/660862625ba8
Fix pinned tab positioning. r=jaws

Comment 9

[Cosmin Sabou [:CosminS]]

Bugs Bug 1700076, Bug 1699691 were backed out instead: https://hg.mozilla.org/integration/autoland/rev/dae7fefaf8278e53d864391a50ae947d5ce5747a

Comment 10

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/660862625ba8

Comment 11

[Negritas Sergiu, Desktop QA]

Hello I have managed to reproduce the issue using Ubuntu 20 with firefox 88.0a1 (2021-03-04), I can confirm that this issue is fixed on firefox 89.0b4 and with fx 90.0a1 (2021-04-27). I will update the flags accordingly.

Thank you!