As exciting as watching paint dry
Cyrille fixed a bug in Krita's watercolor simulation yesterday. This is a special colorspace, based on Raph Levien's Wet Dream prototype. Raph wrote this code for eventual inclusion in the Gimp, but it never got that far.
During my lunch break today I discovered why our automatic drying left nothing but small one-pixel wide trace of your last brush stroke: we flowed, dried and adsorbed the previous state of the canvas, instead of the state right after painting. The temporary fix is to make every drying step an undo stage. This sucks, but at least allows automatically drying of your wet paint:
And all this work for something that nature does without any effort!
(Note that Krita already does something Corel Painter has only learned in version IX: save and load the wet state of your painting. Close Krita, start again, load your image and it continues drying until completely dry.)