Disappearing windows

[mmost01]

BEFORE YOU BEGIN

I have attempted the following troubleshooting suggestions:

• [+] The issue persists when using Firefox in Troubleshoot Mode.
• [+] Disabled DNS-level content blocking (AdGuard Home, NextDNS, Control D, RethinkDNS, PiHole, etc), cleared my DNS cache, and used my ISP's DNS resolver (if applicable).
• [+] Cleared website data, restarted Firefox, and my issue persists.
• [+] I have created a new profile. The issue persists when using the current user.js file on GitHub. (Must be in a new profile and a new user.js!)

REPORT

When split two tabs into two windows and minimize windows, only one will left in taskbar, and all other will dissapear

To Reproduce
Steps to reproduce the behavior:

1. Open two windows (f.e. youtube and facebook)
2. Drag one of the tabs to move it to a new window.
3. Minimize both of them
4. Try to open them from taskbar, but only one will be here.

Expected behavior
Several windows are seen in taskbar

Desktop (please complete the following information):

• OS: Windows 11
• Browser: Mozilla Firefox
• Version: 134.0.1

Additional context
There was no this problem in user.js version 119