Tabs not visible on tab bar after restart

[pgrafix]

Describe the bug

After updating to FF 141 - 141.2 tabs of a tab group are not displaying on the tab bar [of a restored window] when the browser is restarted. The tabs are still within the group and I can cycle through the tabs with the keyboard, but the tabs themselves never display on the tab bar (regardless of FF horizontal or vertical tab setting).

To Reproduce

Steps to reproduce the behavior:

1. Update to FF 141 or greater (up to 141.2 as of posting).
2. Upon restart the last open group doesn't display all of its tabs in the tab bar.

Expected behavior

Tabs in last open group should display normally within the tab bar after restart.

Desktop (please complete the following information):

• Mac OS 12.7.6
• Firefox version: 141.0-141.2
• Simple Tab Groups version: 5.3.2

Additional context

If I open any of my tab groups in a new window, the tabs will display in the tab bar as expected. However, again upon restart, the tabs will not display on the tab bar. Only fix was to roll back to FF 140.0.

[ozhound]

+1 here for me too same FF version