When i use firefox to use tweenmax on an jquery object that is currently display:none (and iframe's parent is display:none) i get the following error: TypeError: _getComputedStyle(...) is null TweenMax.js:3874:37   To make it work i changed the code of TweenMax.js (1.20.2) line 3874 to: if (_transformProp && ((none = (_getComputedStyle(e) == null || _getComputedStyle(e).display === "none")) || !e.parentNode)) {   Related firefox bug: https://bugzilla.mozil