Upon upgrading from flash-plugin-10.3.162.29-0.1.el6.rf (x86_64) to
flash-plugin-11.0.1.60.0.1.el6.rf (x86_64), when i switch to full screen
mode when playing a video on for example youtube Xorg freezes.
When using flash plugin 10 the use of "OverrideGPUValidation=true" in
the /etc/adobe/mms.cfg file fixed the problem. Though it does not fix
the problem on flash-plugin 11.
If the compiz window manager is used fullscreen playback works.