The title and the attached picture show the problem. I use Windows 10 with 64-bit and Acorbat Pro. Everything is up to date. I have tried everything I could find on the www, but to no avail. Preview pane and everything else works fine, just the desktop icon looks ugly. Even if it is a cosmetic problem, I wonder why it worked with 32-bit and why it seems to work with Windows 11, at least on my wife's notebook.
It just doesn't look nice with the white background.
Maybe it's quite easy to fix by Adobe programmers. Would you please have a look at it.