SUMMARY
Since receiving the 4.2.1 update, my pressure sensitivity doesn't work for any tool or brush I try to use. I've attempted to fix this by adjusting the options under both 'configure Krita' and 'configure toolbar,' but neither have had any effect. I've tested out another drawing program on my computer, and it doesn't appear to be a problem with my tablet (an XP-Pen). I've had Krita for almost a year now, and I've never experienced this problem before, so I can only assume it has to do with the new update.

STEPS TO REPRODUCE
1. Open up a Krita document
2. Select any brush 
3. Do a simple sketching motion on tablet

OBSERVED RESULT
The brush (no matter what it is) behaves like a badly bleeding marker; there is no control over line thickness, opacity, or flow. You may as well be drawing with a computer mouse.


EXPECTED RESULT
The brush creates a sketch-like line that goes from thick to thin, according to the amount of pressure applied. A nearly 1:1 recreation of the pen stroke.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
I use the Windows version of Krita. Thank you for your time, and if you need any additional information, please shoot me an email.