[_manifold]

Throwing in my support for Krita.

I suppose it just depends on what you need in an image editor but in my opinion GIMP has been dead in the water for well over a decade at this point.

Krita on the other hand has a pretty rich feature set and seems to be more actively developed - I just wish it were more performant and a bit less quirky, interface-wise. I still use it on a regular basis though.