silvestreh/onScreen — pull request #22 by pstierhoff (2014-11-21 20:39:03+00:00)
Title: remove placeholder after image loads

The background image gif causes continuous repaints even when not visible and can affect overall performance of other animations (see http://www.html5rocks.com/en/tutorials/speed/animated-gifs/). It should be removed after the image has loaded.