Comment 108 for bug 1292398

Davias (davias) wrote :

Ok I got it! I was about to implement this solution (thanks for this one, even it was a patch I did not like to use) when I was enlighted by this: Gnome is not getting monitor IDs correctly. I have 2 digital BenQ and one analog Asus. If I run Ubuntu 16.04 (on Gnome Fallback) System settings, they are identified correctly, albeit in the wrong position (note: right after login, the monitor position is set correctly for a few seconds, then when desktop is loaded, is messed up again). So, I execute step 1 of the above solution, deleted monitors.xml, installed gnome-control-center and run it: the monitors where wrongly identified. I changed monitor position using the wrong IDs for the monitor, getting them were I wanted. Then just shut down and re-boot...voilĂ : after login the desktop was loaded with correct monitor position for all the 3 monitor!

Hope this can shed some light on this annoying Ubuntu bug...the fact that Ubuntu system settings/monitor and gnome-control-center IDs monitor in different ways is clearly the problem. I remember something similar when using Catalyst Control Center in 14.04 with fgrlx: could not get it to set it right - then, using system settings/monitor, I was able to fix it - and it stayed there until the upgrade to 16.04.