Created attachment 88304 [details]
debug logs

Hi, it was suggested that I post an issue I've encountered using my tablet's stylus buttons in Krita.

Relevant System Specs:

Windows 8.1 Pro
Krita Version 2.8.3 (git c49997b) (x64)
Huion H58L Tablet and Stylus
(Logitech MX518 Mouse)

The Krita main canvas does not respond to stylus rocker buttons when they are assigned to mouse functions (although the dockers do respond to such button presses). For example, when these stylus buttons are assigned to middle and right click, Krita will not respond to these as it will when the same clicks are issued from my mouse (pan canvas or popup palette). Interestingly, it will accept these stylus button presses if they are mapped to keyboard keystrokes. Outside of Krita, for the most part, the stylus buttons can be mapped to mouse clicks and will function as expected. My browser, Microsoft Paint, the Windows desktop, etc, all work as expected. However, there are some other drawing applications which behave the same way as Krita (GIMP, FireAlpaca) although one application (Artrage) seems to work as expected with the stylus buttons.

Also, there is actually a way I can get Krita to respond to the buttons of the stylus. But in doing so, Krita no longer responds to pressure sensitivity. It all depends on whether I start up Krita using by clicking with my stylus (and avoiding touching my mouse). I have captured tablet debug data for 3 different situations. I have attached the logs.

1. Krita is opened as usual with the mouse. It is responsive to stylus pressure, but will not accept stylus button presses which are mapped to mouse clicks.

2. Krita is opened by tapping the shortcut with the stylus. In this case, it responds to the stylus rocker buttons but there is no pressure sensitivity until I move the mouse. Then the tablet behaves as previously explained with full pressure sensitivity but no stylus buttons presses are registered.

3. Krita is minimized and then I use my stylus to tap back into it, the stylus rocker buttons work fine, but once I tap my stylus on the canvas, they no longer work.

Regrettably I lack the technical knowledge to troubleshoot much deeper, but I did notice two interesting things within the debug logs generated: that Krita is logging both mouse and tablet QEvents (whatever that is) when I'm simply using my tablet stylus, as well as the fact that [BLOCKED] appears on many QEvents, including the stylus button presses which Krita doesn't respond to.

Due to the fact that it only seems to affect applications which call upon the tablet's pressure sensitivity, I feel it's most likely that this issue is caused by either Huion's drivers or Windows itself.