Very informative, thanks. In native land we can listen to mouse motion but it is more CPU friendly to have a timer and poll the mouse position periodically, par

Very informative, thanks. In native land we can listen to mouse motion but it is more CPU friendly to have a timer and poll the mouse position periodically, particularly if the location of the cursor causes further processing (like working out what data to display in a popup hint). The good thing with the mouseEnter / mouseLeave is that you can stop the timer and only restart polling when they enter again. Is there a way of doing this on web pages or is it really still just callbacks for mouse motion?