The latest update on the XFCE13 RC has cased my display to skew.
Started getting screen (like vertical hold on old TVs) with Black bar at bottom and whole screen seems to be moved up (out of sync?) easily fix using monitor auto adjust or setting>display.
But after reboots/login and out, sometimes fine sometimes back to problem (seems random).
Now getting correct height but black bar on right of screen every thing pushed left (icons on desktop and panel cut off) not pushed up.
P.S. this is a new stock install with MDM still being used.
Edit went back normal (may be hardware 'external monitor connected thru dock' and a 'Hybrid SSD Hard drive)