QGLPixelBuffer: In order to check if the system has support for pbuffers it creates a QGLWidget, it would be nice if it was possible that it didn't do this. If it is not possible, then the documentation should be updated to reflect that it can't be done without creating a QGLWidget and therefore the necessary restrictions are imposed as a result.

Also, it would be nice if it was possible to use QGLPixelBuffer without the need for a QGLWidget, since it is used for rendering off-screen and would be nice if it could be used without a dependency on a QGLWidget at all.