Lock drawn masks position
Sometimes, when you play with drawn masks in the darkroom, it happens that several masks overlap or are very close to each other. This makes it unreliable and tricky to select and edit (move, resize) one mask without grabbing the wrong one by accident. With masks drawn precisely on sharp edges, a slight move can mess up completely the result.
It would be nice to be able to lock some masks prior to the edits on the others, in a "belt & suspenders" manner.