This started a couple versions ago, shame on me for not reporting it sooner.
Previously I could edit a mask in quick mask mode if that mask was disabled. This allowed me to see the original data beneath the red overlay for edge refinements. When I do this now, it does not register any brush marks at all, and some times will give a glitch, half-affected area where my brush was that doesn't in turn edit the actual mask until I turn quick mask off.
Would love some help problem solving this or having the bug acknowledged! Thanks