P: Eliminate replace/merge window when copy-pasting

It's been 4 years and this popup still annoys me to no end. This should be a checkmark in the masking dock, or in the sync settings. 

I'd say it is often necessary or wanted. Suppose you have two landscape images. On the first one you create a sky mask. You copy this mask and some other settings. In the second image you created a subject mask. If you decide to paste the settings of the first image onto that second image, would it make sense that the pasted sky mask replaces the subject mask? I'd say that does not make any sense at all. You want both masks, so you want to merge.

That doesn't mean it could not be done without a second click, however. A modifier key might be a better way.

couldn't agree more; merging masks means you're essentially doubling your mask intensity, and how often is that necesary or even wanted? It feels like a pointless but mandatory click, over and over again. There should at least be an option to remove the option. 

Got to say that it is very annoying feature which cuts a flow.

I think people often merge their copy-pastes. Merge means that a copied mask does not replace other masks, but is added to the other masks. That makes a lot of sense for masks...