[Regression 1.8b+] Multiple tab issues regarding extensions

[vicky5124]

Captchas

• I have read the instructions.
• I have searched existing issues and avoided creating duplicates.
• I am not filing an enhancement request.
• I have checked that this issue cannot be reproduced on Mozilla Firefox.
• I have checked that this issue can be reproduced once I removed all my Mods and Custom CSS.

What happened?

Reopening #5844

After updating past 1.7.6b to any of the 1.8b and above versions, managing tabs with anything that isn't native completely destroys the browser.

• Obtaining the list of tabs more than once with the extension API makes all the tabs disappear; the API doesn't get any tabs (not even pinned), and the native tab bar stops showing the tabs too; not even new tabs show up. Possibly related issues include:

  • New Zen Browser version (Firefox v135) bug mbnuqw/sidebery#2024
  • Workspaces except the first one lost all open tabs after 1.8b update #5662

• The tab order is really messed up; trying to switch the position, or selecting tabs with an extension, moves the tab or selects the wrong tab with an offset of N (= number of pinned tabs) positions lower (higher in the list when using vertical tabs, to the left in horizontal) than the provided tab position. Possibly related issues include:

  • Dragging pinned tabs to reoder them puts them in a random place #5754
  • Middle clicking some links opens them as glance instead of in a new tab #5823

• There's also a HUGE memory leak when pinning a tab, or selecting a tab that underflows the tab position through an extension (managed to get Zen to use up 27 GB of ram in 2 minutes). Only the previous point is a possibly related issue.

• There's also some really odd behaviour with hidden and unloaded tabs that I can't make any sense of, but it appears that trying to hide, unhide, load, or unload tabs through extensions or natively occasionally recreates the tabs entirely, or messes up the metadata in a way that extensions can't make sense of it, which can clear any additional metadata the tab may have from the extension (such as which tab tree it is at, what folder it is at, last access time, title, etc...), or make the tab disappear from the extension; this issue is especially bad on pinned tabs. Possibly related issues:

  • The Tree Style Tab extension does not refresh the tab list when switching workspaces #5831
  • Dragging pinned tabs to reoder them puts them in a random place #5754

• Other possibly related issues:

  • Tabs move to bottom on start up #5869

The issues listed above are OS-agnostic.

All the issues listed are present with an entirely new profile, no mods, and any one of the listed extensions below.

Everything works perfectly fine in 1.7.6b, but everything is broken on 1.8b and newer versions. None of the patches and fixes in the following releases seem to fix any of the issues, outside pinned tabs duplicating.

I have tested all the tab management extensions that I know of:

• Sidebery (Firefox)
• Sidebery (Zen) (regardless of the presence of the mod)
• Tree Style Tab
• Tab Stash
• Tabby
• Tree Tabs

These issues do not happen on any Firefox version (tested from 133.0 release to 138.0a1)

Version

1.8b 1.8.1b 1.8.2b 1.9b 1.9.1b 1.10b 1.10.1b 1.10.2b 1.10.3b + Twilight

What platform are you seeing the problem on?

Linux (AppImage), Linux (Tarball), Windows - x64

What component is this issue related to?

Extensions

Relevant log output if applicable

[mauro-balades]

Might had been fixed with #7064. Could you please check again on twilight?

[unkn0wncode]

Might had been fixed with #7064. Could you please check again on twilight?

on latest 1.10.3t (Firefox 137.0) (2025-04-01) (aarch64) in sidebery tabs are still completely not visible.
Restoring any session from third party addons like sidebery and then closing the window also results in freeze and crash.

[Artii-G]

It seems that this issue is old and hasn't been addressed. I use Sideberry, as it is still the best tab management tool ever. Making a mess with tabs is terrible for workflow. I previously used Floorp but stopped because it has issues with loading certain websites, and the bugs are not being resolved. If the Zen developers don’t care about fixing this issue, I will leave it immediately.