I mostly use a Wacom tablet instead of a mouse in all applications. After a proper setup, with X11 it worked great. With Wayland it works sufficiently well, but I really miss the ability to scroll with the tablet’s stylus by pressing a stylus’s button and moving the stylus up/down/left/right to scroll up/down/left/right. Just like a scrolling emulation with a mouse or a trackball.
Fortunately, I found patches that implement a scroll emulation in libinput: GitHub - tux3/libinput-wacom-scroll: Scroll button support for Wacom tablets . After applying the patches, when I press
the stylus’s button and move the stylus, libinput generates a scroll
as can be seen in libinput debug-gui and verified with libinput debug-events: POINTER_SCROLL_CONTINUOUS (instead of TABLET_TOOL_AXIS / TABLET_TOOL_BUTTON when just moving the stylus / pressing the button).
Unfortunately, it doesn’t scroll in any app. When I try to scroll, the cursor doesn’t move (just like the scrolling emulation was working—great!), but nothing is scrolled (
).
I don’t know the device-to-cursor stack well, but I assume the problem of no scroll is related to Gnome or mutter. Am I right?
Is it a bug or a missing feature? Can it be fixed/implemented? How? Where to look for it in the source of Gnome/mutter? …?