When I try to execute beryl I receive this error:
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* Beryl system compatiblity check *
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Detected xserver : NVIDIA
Checking Display :0 ...
Checking for XComposite extension : passed (v0.3)
Checking for XDamage extension : passed
Checking for RandR extension : passed
Checking for XSync extension : passed
Checking Screen 0 ...
Checking for GLX_SGIX_fbconfig : passed
Checking for GLX_EXT_texture_from_pixmap : failed
No GLX_EXT_texture_from_pixmap
beryl: Support for non power of two textures missing
beryl: Failed to manage screen: 0
beryl: No manageable screens found on display :0