can’t copy and paste or drag an image file in to the app as well but someone using Linux mint in the discord did (only the copy and pasting and not dragging). I am assuming that it’s more of a wayland problem since Linux mint is x11
Mint 22.1 Cinnamon, pasting doesn’t work until selecting another layer (that also sometimes doesn’t work ) You could try doing that, and see if it works
In my experience if you wait a bit before selecting the second layer there are higher chances that it will paste