I also run Win 11 and ver 115.4.1 and am having no difficulties. There may be some other reason for what you are experiencing. Possibly someone else here will have some insight on that.

Does the same thing happen in safe/troubleshoot mode (hold Shift when launching TB)?

Unfortunately I get the same problem; thank you for suggesting it.

I've never experienced this, but it seems there are a number of possibilities:

https://www.groovypost.com/howto/windows-key-not-working-in-windows-11/

Unfortunately these have not solved the problem.

The suggestions did not solve the problem. However one included creating a restore point; once I had tried the suggestions I did a restore back to before running a script. The Windows key now seems to work OK!

I also have this identical problem. As soon as I close TB, the Windows key function is restored. Had previously tried all the online suggestions from YouTube vids, windows support, and internet tech sites... game mode, keyboard settings, command line tweaks, etc, etc with no luck. Finally, just tonight used Task Manager to stop apps & processes one at a time and as soon as I stopped TB, Win key function returned. Verified this by closing TB normally through the app, and sure enough, same result. As soon as I open TB again Win key function ceases. I really like TB and I use multiple desktops with the Win Key shortcuts to switch between them. It would sure be nice to get them to play well together. Win 11 home v. 10.0.22621 TB 115.6.0 UPDATE: I originally didn't think the restore point procedure would work in my case, because the oldest restore point I had was newer than the onset of the problem (new computer). I did try it though, and it seams to have worked. Win key is working fine with TB open. The restore caused TB to regress from 115.6.0 to v. 115.5.1, which leads me to believe it's a problem with the latest TB update.

Re JJRam: As outlined in my post on 30th October, creating a restore point then reinstalling windows from the restore point solved the problem. Since then, Win key & thunderbird have worked together without any problems.

Same problem. Here's more information. After starting Thunderbird, Windows Key continues to work until additional messages are read--then it becomes dead until you exit Thunderbird, and then it starts working again. I've tried Safe Mode and disabling all my add-ons--no effect. Thunderbird version is: 115.6.0 (latest). Windows 11 version: 23H2(OS Build 22631.2861). This bug makes Thunderbird incompatible with Windows, and it is very annoying. I'm not going to restore to a previous version of Windows/Thunderbird to work around what is clearly a Thunderbird bug--fix the bug!

Similar and I cannot use thunderbird now. Just sits in the tray with a blue line underneath, a minature version of my TB sits and nothing when I click it, and the blue circle spins

I am having this problem as well. I am on Windows 10 Pro build 19045.4046, experience pack 1000.19053.1000.0 running Thunderbird version 115.8.0 (32-bit). Any updates on a fix or workaround that doesn't involve downgrading would be much appreciated as I couldn't find any usable restore points :( Thanks :)

I found that creating a restore point, then restoring the system to that point, solved the problem. This was on a Windows 11 system; hopefully it would work on Windows 10 as well.

I have same Problem with windows 10 115.8.1 So no solution till now right? Will mozilla fix this for future versions?