Paint.net is my go-to image editing software. I'm not a digital artist or professional photographer, I just need to downsize/crop/adjust the occasional image. I don't need the kitchen sink. Regular MS Paint is annoyingly basic and Krita, GIMP, et al., are too much UI-wise. That said, I use Linux daily but not for images so not sure if there is a Paint.net analog on Linux already.

Back when I was still on Windows(XP days), I made heavy use of Paint.net. Given Microsoft’s penchant for gobbling up smaller companies, I was always a bit surprised that they never bought the company and integrated paint.net as the built-in OS replacement for the original MS Paint.