Looks like I found the answer in the next video! They were artifacts of Random Walk. All I needed to do was change to Fixed Radius. Problem Solved.
Indeed looking great!
And to confirm the confusion:
What used to be Random Walk in 2.93 and before is now, in 3.0+, Random Walk (Fixed Radius).
The (simple) Random Walk in 3.0+ is new! It adjusts the Radius according to the Base Color. (I honestly can't figure out yet, which would be closer to reality...)
So far I prefer the old one, now called Random Walk (Fixed Radius), The same radius values in the new Random Walk, cause blown out colors far from the painted color. My guess would be that it occurs mostly where there is an abrupt change in the painted colors along the same line were there is an abrupt change in surface thickness.
I agree, the newer Random Walk is supposed to preserve detail better, but in my tests (with human heads), it washes out (especially the finer) details and creates some blue-greenish glow at some parts (nose and eyelids).
Maybe the newer version requires different treatment, but for now, I stick with the Fixed Radius.
