Hi,
I've installed Krita on my Manjaro linux/Gnu but I've strange behavior from the scrolling up and down of the mouse on the canvas. Sometimes it works sometimes it doesn't. But it works fine on the menu button or on the dockers . I can't manage to find the problem, it's very frustrating. The num. keypad has the same behavior.

Even launched from a console, it doesn't give error messages.

Is this a known issue ?
thanks.

No, this is not a known issue. You could make a tablet log and see if that shows something interesting, but it's pretty much 100% sure to be something local to your system. See https://docs.krita.org/en/KritaFAQ.html#tablets

I've that issue only with Krita so probably a badly set thing but can't find it. The table (XP pen 15.6) works fine in other applications like Mypaint or Gimp. I'm using a HDMI switcher to use the tablet, can it be a source of the issue ?

Gimp and MyPaint use GTK, Krita uses Qt, so the comparison isn't really relevant.