BUG: Tab bar is vertically centered [Archlinux / Wayland-SwayWM / zen-twilight]

[DeveloperGY]

Preliminary Checks

• I have read and understood the important section above.
• 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?

The tab bar content is vertically centered, making it so that if you have many tabs open you can only see a few at once and wastes a lot of space

Expected behavior

Tab bar content grows downwards from the top

Actual behavior

Tab bar content is centered vertically and does not give enough space to properly manage tabs when you have a lot of them

Steps to reproduce

Im not entirely sure what caused it so I dont know how to reproduce it. The only zen mod I have installed is the zen color picker mod (see screenshot) and I am using the zen-twilight-bin package from the AUR package link

Screenshots and videos

No response

Version

1.20t (Firefox 150.0.1) (2026-05-05) (64-bit)

What platform are you seeing the problem on?

Other

What component is this issue related to?

Tabs

Relevant log output if applicable

[DeveloperGY]

I also just updated (after creating the issue) to version 1.20t (Firefox 150.0.2) (2026-05-07) (64-bit) and the issue still persists.

[Propheticus]

Confirmed, can reproduce both on Linux and Windows.
Had noticed and reported it to the Dev earlier today.

[sporocyst]

Should be fixed now with #13610