Paint.Net is by far the best non-pro graphics editor ever. So practical and intuitive. To me lack of Paint.Net seems the biggest problem of desktop Linux, also of Mac. Sadly Pinta appears buggy. But it still is tolerable and has no real alternative. Both Photoshop and GIMP feel too unintuitive and this way take too much time to do simple things when you are not a graphics pro. GIMP also arguably looks ugly. Paint.Net is a great example of the whole UX (intuitiveness, convenience and aesthetics) done right.
As I understand Paint.Net it is a WPF app. I wish the author would just use Avalonia XPF to port it to Linux and Mac. XPF is a drop-in replacement for WPF which can easily make WPF apps cross-platform for some money. I wouldn't mind paying my share.
Yup, Paint.NET was the thing I mourned the most switching from Windows to Linux... still do. I'm somewhat surprised that there hasn't been more of an effort to get it working on Wine. I figure there's some context I'm missing, but still. It just seems odd that so many games have been made to work, but Paint.NET is sitting with a listed rank of "Garbage".
This is a vague memory so I might be wrong, but I think it's WinForms, not WPF, and it makes calls into Windows directly using P/Invoke so it's not trivially portable.
Both WPF and WinForms, additionally at least DirectWrite and Direct2D and by now a bunch of shader code for the various effects. I guess there's a lot of things that can go wrong when trying to run it via Wine.
As I understand Paint.Net it is a WPF app. I wish the author would just use Avalonia XPF to port it to Linux and Mac. XPF is a drop-in replacement for WPF which can easily make WPF apps cross-platform for some money. I wouldn't mind paying my share.