The issue is not completely described. What actually happens is that the icon is of size 512x512 and it’s placed in the wrong location. I have an aliased command to fix that on every update, but I’d like it to be fixed naturally too.
I was able to get the program icon in the KDE task manager using https://github.com/probonopd/go-appimage (I think) and pinning it to the task manager from the application launcher menu shortcut, but found another issue. It seems that each launch of Anytype creates a differently named .mount_Anytypxxxx folder in the /tmp/ directory, and so clicking the icon in the task manager creates a 2nd one for the currently opened session because it’s pointing to that new folder. This is on the latest OpenSUSE Tumbleweed. @Srinath