Just came across another bug.
In Personalization - Colors, "Show accent color on title bars and windows borders" doesn't work properly. The taskbar flashes, Windows borders change color but title bars don't. Waiting for confirmation before I report it.
edit: also, there's a very noticeable delay toggling on/off "Show accent color on Start and taskbar"
Just found out that switching to "Microsoft Basic display Adapter" reduces all delays significantly and accent color on title bars and windows borders now works. Is Windows 11 somehow misusing display drivers?
Could be a similar issue that they have with the Widgets, they work with some display adapters and not others.
On the old Dell Optiplex 380, I had to find a Intel display driver from 2010 and replace the newer one supplied by Microsoft from 2013 and then the Widgets started working... 😉
Had the same issue with MSI laptop that has 2 display adapters, it fails with the Intel but works fine with the Nvidia, had to select Nvidia as preferred adapter instead of leaving it to Auto.
what a mess! luckily no widgets issues for me