[Bug] group-tab.html tabs not auto-expanding first time

[irvinm]

Abstract

Looks like in a recent update, the group-tab.html is not auto-expanding when clicking on that tab and then one of the links in the tree below it. After expanding the tree manually once, the proper behavior is restored. Biggest error I see in the console is around "managed storage is not provided".

Steps to reproduce

I will work on a cleaner scenario if this is not sufficient.

1. Start Firefox with at lease one group-tab.html with some tabs under it.
2. Click on the group-tab.html and click on one of the links to a tab under it.
3. See that the context switches to that tab and it is loaded, but the tree is not expanded.
4. Collapse the tree again and repeat steps 2 and 3 and see the tree now auto-expands.

Video:

2026-03-27.17-29-31a.mp4

Expected result

group-tab.html should always auto expand when collapsed and clicking on a link to a child tab.

Actual result

If never expanded, when clicking on the link the tree is not expanded.

Environment

• Platform (OS): Windows 11
• Version of Firefox: 149.0
• Version (or revision) of Tree Style Tab: 4.2.12

[piroor]

Hmm, I couldn't reproduce this on my environment. Could you collect logs with these log modules?:

• common/tabs-internal-operation
• common/tst-api
• background/handle-tab-focus
• background/tree
• sidebar/sidebar-items

On my environment I got logs like this:

[irvinm]

Here is the working vs. non-working logs. I tried to highlight key moments.

[piroor]

Thanks! Your non-working flow logs says that TST unexpectedly detects the tab corresponding to the clicked item (a child in a collapsed tree) as "not collapsed" - it means that the tab has no "collapsed" state flag in the background (controller) script, even if they are actually collapsed in the sidebar. It is very odd...

I think it is not a problem around group tab, but a problem around session restoration. All tabs under collapsed tree should be restored with "collapsed" state in both background and sidebar scripts, but on your case the background script unexpectedly lose "collapsed" state of tabs.

[piroor]

Could you try to give focus to a collapsed tab which is not under a group tab, via the Firefox's native tab bar? I guess that the problem will be reproduced on the case too, if TST lost "collapsed" state of collapsed tabs in the background script.

[piroor]

One more... the log says that the tab corresponding to the clicked link is treated as it has one or more children. This also indicates that restored states of tabs are broken widely.

Which method of session restoration of Firefox do you use?

• FIrefox's option: Settings => General => Startup => Open previous windows and tabs
• App menu => History => Restore previous session
• Or others

[irvinm]

Which method of session restoration of Firefox do you use?

* FIrefox's option: Settings => General => Startup => Open previous windows and tabs

* App menu => History => Restore previous session

* Or others

I just set "Open previous windows and tabs" in the settings. I will get you the other information shortly.

[irvinm]

One more... the log says that the tab corresponding to the clicked link is treated as it has one or more children. This also indicates that restored states of tabs are broken widely.

No, I am not sure that is the case. I do have some "trees" inside of the group-tabs. I believe the example below is what I did for the logs.

[irvinm]

Could you try to give focus to a collapsed tab which is not under a group tab, via the Firefox's native tab bar? I guess that the problem will be reproduced on the case too, if TST lost "collapsed" state of collapsed tabs in the background script.

I can confirm this happens as well. I created 4 tabs. Placed 1 at the root with 3 children (collapsed). I clicked on the parent, then clicked on one of the children from the native tab bar. The child was loaded as the active tab, but the TST side bar never expanded.

[piroor]

Thank you for detailed information!

After trials I've confirmed that the problem happens on TST 4.2.12 but does not on the latest development version.
I think changes of the PR #3893 (it is a part of TST 4.3.0 which is under reviewing) may fix this problem silently.

[irvinm]

Thank you @piroor. I'll check it out after 4.3.0 is released to verify.