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Changes between Initial Version and Version 1 of Ticket #1615, comment 3

initial	v1
1	1	The "Xpra Virtual Touchpad" device is working and enabled as of r18918 (just needed to figure out the magic incantation for uinput)
	2	r18928 allows us to disable the "touchpad" and "pointer" virtual device initialization individually.
2	3	We normalize the coordinates using the virtual screen size, maybe this should be using the client's screen size instead? Or some other reliable unit?
3	4