[Bug]: Vertical Tab bar malfunctioning

[universish]

Pre-Submission Checklist

• [X] I have checked the existing/closed issues to ensure this issue has not already been reported.
• [X] I am using the latest supported version of the browser.
• [X] I have tried disabling all browser extensions/add-ons to rule out interference from these.
• [X] I have tried clearing the browser cache and cookies.
• [X] I have checked with a new profile and the issue still occurs.
• [X] I have provided detailed step-by-step instructions on how to reproduce the issue.
• [X] I have included relevant screenshots or console outputs.
• [X] I have checked that this problem is not occurring in the latest version of Firefox ESR.
• [X] This issue is specific to this browser and does not occur in other browsers.

Bug Summary

With the vertical tab bar feature turned on, floorp --> settings --> Design --> Tab Bar features are broken, not working properly.

Reproduction Steps

1. settings
2. Design
3. "Vertical Tab bar" activated
4. Tab Bar

Expected Behavior

It should work properly.

Actual Behavior

Problematic panel sizes

Screenshots

Browser Version

11.19.1

Operating System

Windows 11

Additional Context

No response