I have two computers running Windows 11, a laptop and a desktop. Both have this issue. I believe the laptop had this issue right after doing a clean install. Probably the 1st or 2nd boot.
I have previously used the restart explorer.exe method to fix it. I also use multiple virtual desktops and switching between them sometimes is the cause of the issue, but is also sometimes the fix.
As such, I would advise everyone to stay away from invasive "fixes" like dsm repair or OS upgrade, or a reinstall. Most likely it will happen again regardless. I can't believe how MS cannot fix such a small bug in the most used UI of the OS for so long.
For anyone wanting a permanent fix, I think you'll have to install Windows 10...