Comment 21 for bug 938758

The problem is more general. I believe it is related to the xf86 interface the driver uses to report input events to Xorg.

I'm experiencing the same thing with the alternative xf86-input-mtrack driver on github (https://github.com/p2rkw/xf86-input-mtrack). I searched in the code and there is nothing particular that prevents the events from being reported while trying to push the cursor off the screen. The only thing that is common between this tablet driver in this topic and the touchpad driver I'm having trouble with, is the xf86. The default synaptics touchpad driver that comes with Ubuntu, obviously does not have this problem, and also does not use xf86.