https://bugs.winehq.org/show_bug.cgi?id=55513
--- Comment #7 from C. Leu kle@bluewin.ch --- Yes I can confirm this behavior. Many thanks @Jeff Smith for bisecting the problem.
Paint.NET 3.5.11 is working stable in Wine 8.15 when Mono 7.4.1 is used. Great! So I have simply uninstalled Mono 8.0.0 and then installed the older build from here:
https://github.com/madewokherd/wine-mono/releases
So should I now also close this issue here? It looks that this is a problem in Mono 8.0.0 and Mono 8.0.1.
The only last minor flaws in Paint.NET 3.5.11 is that the "miniature-view window" (on the right corner above) do not shows anything. But it starts to work when the Windows version is set to "Windows XP". But this is again another topic. ;-)