xauth file / .Xauthority

[1wilkens]

Currently an xauth file is generated and written to disk but not used when launching X, because the concept of .Xauthority is not quite clear. Adding the flag to the launch prevents gtk from opening the display. This is weird because the main ui (via gtk) will always be executed as root and as such should have access to X under all circumstances.

Also it is just not clear what .Xauthority actually does. In theory it should limit access to the X server but the auth file via startx actually contains multiple magic cookies while .Xauthority only contains 1.

More research is required to figure out what the "best practices" are.
Although this is an enhancement it is the de-facto standard in all other display managers so it is a blocker for v0.1