1917069 - Dragging tabs animations broken for horizontal tabs in RTL mode when switching directionality without restarting

Status: VERIFIED FIXED

(Firefox :: Tabbed Browser, defect, P3)

Description

[Nikki Sharpley (:nikkis) (she/her)]

Attachment: Screen Recording 2024-09-05 at 2.47.18 PM.mov

See screen recording.

Comment 1

[Dão Gottwald [:dao]]

Uh-oh, would you mind running mozregression to see when exactly this broke? I suspect I may have broken this in bug 1914519...

Comment 2

[Nikki Sharpley (:nikkis) (she/her)]

Mozregression wasn't really helpful. It suggested 4th September as the date of regression, but I don't see any changes that would've affected it here:

app_name: firefox
build_date: 2024-09-04 04:44:55.474000
build_file: /Users/nsharpley/.mozilla/mozregression/persist/9091ecd6aef9-debug--autoland--target.dmg
build_type: integration
build_url: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/RixbMix8RnWPJfxKh2m94Q/runs/0/artifacts/public%2Fbuild%2Ftarget.dmg
changeset: 9091ecd6aef987b2da1451e958e5fe7b4db1421e
pushlog_url: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=95497826aba24fdf743d0926c26e074a3ec11f40&tochange=9091ecd6aef987b2da1451e958e5fe7b4db1421e
repo_name: autoland
repo_url: https://hg.mozilla.org/integration/autoland
task_id: RixbMix8RnWPJfxKh2m94Q

Comment 3

[Gregory Pappas [:gregp]]

When I set intl.l10n.pseudo to bidi at runtime, tab dragging breaks. After restarting Firefox, tab dragging works fine in RTL mode.

So, the issue might only be with live direction switching. Perhaps this should block bug 1761758?

Comment 4

[Dão Gottwald [:dao]]

(In reply to Gregory Pappas [:gregp] from comment #3)

When I set intl.l10n.pseudo to bidi at runtime, tab dragging breaks. After restarting Firefox, tab dragging works fine in RTL mode.

So, the issue might only be with live direction switching. Perhaps this should block bug 1761758?

Sounds good, thanks!

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

Based on comment #2, this bug contains a bisection range found by mozregression. However, the Regressed by field is still not filled.

:sfink and :noriszfay, since you are the authors of the changes in the range, if possible, could you fill the Regressed by field and investigate this regression?

For more information, please visit BugBot documentation.

Comment 6

[BugBot [:suhaib / :marco/ :calixte]]

This bug has been marked as a regression. Setting status flag for Nightly to affected.

Comment 7

[Steve Fink [:sfink] [:s:]]

It seems very unlikely to be related to my patch, but I reproduced the issue locally and verified that the new error path I added was not getting hit.

Comment 8

[:Gijs (he/him)]

At least one issue here is likely to be that RTL_UI is cached and not updated when switching languages.

Comment 9

[Dão Gottwald [:dao]]

(In reply to :Gijs (he/him) from comment #8)

At least one issue here is likely to be that RTL_UI is cached and not updated when switching languages.

I suppose we should be observing intl:app-locales-changed.

Comment 10

[Dão Gottwald [:dao]]

Attachment: Bug 1917069 - Make the tab strip handle live language switching between LTR and RTL. r?gijs

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/595e1fb27459
Make the tab strip handle live language switching between LTR and RTL. r=Gijs,reusable-components-reviewers,hjones,fxview-reviewers,sidebar-reviewers,sfoster

Comment 12

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/595e1fb27459

Comment 13

[Rares Doghi, Desktop QA]

Verified as fixed in our latest Nightly 139.0a1 (2025-04-09), I also did a bit of exploratory testing around this, moving multiple tabs and creating tab groups by drag and drop also works correctly, moving Tab groups also works great, which in older builds Moving a Tab group would not show it under the mouse cursor.

I Will update the other affected flags in case this issue will be uplifted.

Comment 14

[BugBot [:suhaib / :marco/ :calixte]]

The patch landed in nightly and beta is affected.
:dao, is this bug important enough to require an uplift?

• If yes, please nominate the patch for beta approval.
• If no, please set status-firefox138 to wontfix.

For more information, please visit BugBot documentation.

Comment 15

[Rares Doghi, Desktop QA]

Updating the main status flag.