When an element is invisible, calling .css('height'/'width') sometimes resets flash movies in the parent element.

In jQuery.css(), near line 1432 and 1439, it changes the position style of the parent element, which causes flash movies to be reset (at least in firefox)

To observe the reset of flash movies caused by change of the "position" style, visit http://www.youtube.com/watch?v=pO5_3tqH09c and add style="position:relative" to body using firebug. You will see the video restart.