Increase number of supported buttons in Mouse Buttons controller to 32
Maybe I was doing something wrong, but when using e.g tablet with extra buttons, current limit of 12 is easily exceeded. In my case I have a tablet with 10 or 12 buttons, plus two on the pen. I remapped them to separate events so they don't coincide with mouse buttons. In Gimp I was unable to assign any function to them, but simply extending the array in app/widgets/gimpcontrollermouse.c
does the trick for me.
I tried to use Linux Input
controller, but it also can't handle the events correctly. Even though libinput reports all the buttons present in console, I don't see them in configuration dialog. It should also probably be modified and the best way would be to dynamically list all available libinput events.