1947758 - Moving a tab into a tab group using Ctrl+Shift+PageDwn breaks the tab group indicators

Status: VERIFIED FIXED

(Firefox :: Tabbed Browser, defect, P1)

Description

[Vincent]

Attachment: The problem using vertical tabs.webm

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:135.0) Gecko/20100101 Firefox/135.0

Steps to reproduce:

1. Add a tab to a tab group
2. Create a new tab, outside that tab group
3. Drag the tab to the position before that tab group
4. Press Ctrl+Shift+PageDwn to move the tab into the tab group

Actual results:

With vertical tabs:
The tab is part of the tab group, but the label of the tab is below the tab, and the coloured line indicating which tabs are in the tab group doesn't extend to the new tab.

With horizontal tabs:
The tab is part of the tab group, but the label of the tab comes after the tab. It does get the coloured line indicating that it is part of the tab group.

Expected results:

The tab is visually part of the tab group.

Comment 1

[Vincent]

Attachment: The problem using horizontal tabs.webm

Comment 2

[DJ (:dwalker)]

Attachment: Bug 1947758 - improve group handling in gBrowser.moveTabForward/Backward. r?dao

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4e2106fbb54e
improve group handling in gBrowser.moveTabForward/Backward. r=dao,tabbrowser-reviewers

Comment 4

[amarc]

https://hg.mozilla.org/mozilla-central/rev/4e2106fbb54e

Comment 5

[Bianca Hidecuti, Desktop Test Engineering [:bhidecuti]]

I was able to reproduce the issue on an affected Firefox Nightly 137.0a1 build from 2025-02-12 using Ubuntu 22.04, while following the steps provided in Comment 0.
Verified as fixed using Firefox 137.0b2 on Windows 11, macOS 13 and Ubuntu 22.04. The tab is now visually part of the tab group.