https://bugs.freedesktop.org/show_bug.cgi?id=79551
--- Comment #7 from Michel Dänzer michel@daenzer.net --- (In reply to comment #6)
if in /etc/environment set DRI_PRIME=1 and in /etc/xprofile set xcompmgr -c & some apps will display with artifacts (part of window freezes when scrolling)
Apps using PRIME, or others?
BTW, just xcompmgr -a should be enough, no need for -c.