[Gimp-developer] bug? xsetwacom setting MapToOutput breaks mouse functionality in 2.9.5

[Casey Connor <gimp-devel-list caseyconnor org>]

Hi -- I use three monitors. My wacom tablet works great, and I can also 
use my mouse to draw in the GIMP image window. When I try to map the 
tablet to a single screen (with my image window) it breaks the ability 
of the mouse to draw on the image.

Calling

xsetwacom --set "Wacom Intuos PT S 2 Pen stylus" MapToOutput next

...maps the tablet to the single screen appropriately, and the tablet 
continues to work great, but the mouse can no longer be used to draw on 
the image (it works fine for menus, tool windows, etc.) If I quit GIMP 
and restart it, the problem persists: tablet is fine, mouse is still 
broken for image editing.

If I unplug the tablet and plug it back in, everything works fine again, 
but the tablet is now mapped to all three screens again, and remapping 
it breaks the mouse again. If I MapToOutput before starting GIMP, it 
just breaks it at the start. Calling "MapToOutput next" repeatedly until 
the tablet is again mapped to all three screens also does not help: once 
it breaks, only unplugging the tablet will reset the buggy state.

Tested with a fresh portable AppImage from pixls.us, and from the otto 
repository (commits 2224733 and 257a4ceb, respectively.) Kubuntu 16.10, 
kernel 4.8.0-46-generic, xsetwacom 0.33.0, using a Wacom Intuous Art Pen 
& Touch Tablet (CTH-490).

Thanks for any thoughts! I will report it as a bug unless someone has 
some ideas that I can try to narrow things down a bit more. Happy to do 
any debugging that will help -- it's so very close to working! If I can 
solve this last puzzle piece it'll be amazing to do photo editing. :-)

-c

P.S. One last detail, in case it's helpful: as the mouse moves the 
cursor into the drawing window, it picks up the location and moves the 
brush outline to that location, but does not update it after that (until 
the next time it enters that window). Similarly, if I try to drag a 
guide from the ruler border, the indicator arrows (in the ruler bars) 
show that it is tracking the cursor location correctly, but no guides 
are dragging around, and none are created when the button is released. 
If I do the same with the tablet, it works fine and makes guides.