Is it possible to duplicate layer masks in Painter? Sometimes I need to mask one same thing on a bunch of layers.
If it's not possible, how to go about re-using a layer mask or selection??
And is it possible to change the opacity of a layer mask?
These are all thing that are very easy to do in Photoshop.
If you want to reuse selections, you should store it in a channel instead of a mask. Channels are layer independent, you can keep reloading the selection
Photoshop does allow you to select the mask with CTRL and copy a mask over and over. But, in my opinion, this isn't how you should be using masks to begin with, if you want to reuse a layer independent selection, you should be using channels.