This question about a ‘pressure sensitivity’ option came up a month ago as well. Pen tablet pressure sensitive
I do like to use my drawing tablet for Darktable regardless, it reduces strain from tweaking sliders with the mouse.
Except I can’t use the mousewheel (can’t even map the tablet macro keys to wheel up or down), so I have to switch to mouse just to change the area of influence size in things like Denoise or Contrast Equaliser.