Here is the thing.
It occurs with the latest versions of darktable, including the 2.6 now installed.
When I use a brush, somehow I am not able to adjust the brush size after. I mean by that, before I was able, once the mask was drawn, to adjust the area affected by the brush, simply reducing the area within the dashed-lines. I used to do that simply scrolling. I can adjust the size before painting the mask, but, once set in place, then I cannot modify the size.
Also, when selecting the “add circle” brush, I am not able to set almost anything besides size (opacity and feather size), moving the mouse while holding the key does not affect the mask behaviour, nor I see the mask changing on screen, as you should when adjusting its opacity. As with the “add brush”, once placed I cannot change its size.
I run the program on a Mac, if useful the information.
Thanks and merry Christmas!
shift-scroll to be consistent with other forms.