When I play any kind of video (or run the screensaver) anything that updates
under the displayed video flickers through the image.
I use Xorg 6.8.0.
MPLayer has a known problem with Composite. Xine works fine.
There are many apps that don't work with the new composite extension in X.org.
To determine if it's a problem specific to xfwm4, you can either:
1) Run xfwm4 without the compositor and try with "xcompmgr -c"
E.g: xfwm4 --compositor=off --daemon && xcompmgr -c
2) Use the Xserver automatic compositor
E.g: xfwm4 --compositor=auto
If the problem remains,with those, then it's not xfwm4 (anyway I'm pretty sure
it's not xfwm4)
As a general note, the compositor/XDamage/XFixes extensions in X.org are pretty
new and considered unstable. If you want to be safe, don't enable the composite
extensions for now.
I'm closing that bug too for the very simple reason that the window manager is
not involved in the VT <-> X switch, it's really between the OS and the X server...
You should direct that bug to http://www.freedesktop.org/bugzilla