Some browsers support
In ticket #9381 you can read why they stopped using
requestionAnimationFrame after some time.
To summarize, problems were that animations didn't run (browsers try to reduce CPU load) when window didn't have focus, which is OK if the window is hidden, but not if it is visible, just out of the focus. Furthermore, animation queues piled up and after window regained focus, things went berserk. This would require ugly changes in the code and/or changes how people add things to the animation queue. So it was decided that support is removed until there is some better way to do this.