Since today when I use the Clone Stamp tool and I want to undo it, it does not show the Undo. The last stroke disapears from the effects but the picture in the viewer does not change. It only disapears when i restart after effects... I Already deleted the preference folder but the behaviour did not change.
I'm under Mac OS right now
Turn off the disk cache and set your comp viewer to Fianl Quality, not Fast preview.
Thank you but this wasn't the solution. It seems that the red giant plug in edge blur interfers with the clone stamp preview...