Comment 11 for bug 90175

There is a bug in xserver-xorg.postinst.in, which assumes that the first line is the actual one we should use. Unfortunately, it seems that this cannot be fixed reliably. If discover doesn't recognize the device (=it isn't mapped to a X driver), output is like this:

nexus6 X11 # discover --disable=serial,parallel,usb,ide,scsi --format="%V %M\t%S\t%D\n" video
parse error reading X server string `unknown'
parse error reading X server string `unknown'
Intel Corporation 82Q963/Q965 Integrated Graphics Controller unknown unknown

(yes, I edited discover-data to not know that card)

so, since you have a video capture device it has a similar output to a "unknown" one, and the script thinks you have an unsupported card and uses vesa. I don't know a way to fix this so that it won't be a) ugly b) reliable.