darktable 3.0 masking inconsistencies & bugs

[kanyck (Nick)]

JFYI:

Difference between "toggle polarity" and "invert mask"

When using drawn masks, there is a “toggle polarity of drawn mask” button that shows either a minus or a plus sign and also a dropdown menu called “invert mask” that can be set to “on” or “off”. They are marked with red in the screenshot below. [Masking] As far as I can figure out, these two do exactly the same. I have tried every combination of masks and these settings I can think of without being able to make them behave differently. Therefore I wonder if there is something I have missed. So…