this problem annoyed me for a while. I always draw with the brush tool and never use the auto-flatten option or (knowingly) any shortcut or button that would flatten my strokes. Yet randomly a couple of drawings end up being flattened making it impossible for me to cut lines with the cutter tool mouse gesture.
I wonder how that can happen? What could I have done accidentely to flatten these drawings? Is this some automatic optimization feature?
I would really appreciate any idea