TypeError: Argument 1 of Window.getDefaultComputedStyle does not implement interface Element

[jmatsushita]

Repost of the following stackoverflow post which includes a workaround: http://stackoverflow.com/questions/24994129/typeerror-argument-1-of-window-getdefaultcomputedstyle-does-not-implement-inter

I have the following code outside my polymer element (in another polymer):

        $(mainThis.shadowRoot.querySelector('#test1')).click(function(e){
            mainThis.$.testelement.openPopup();
        });

The line:

mainThis.$.testelement.openPopup();

Is causing error:

TypeError: Argument 1 of Window.getDefaultComputedStyle does not implement interface Element.

openPopup - is my custom function in polymer "testelement".
The error appears only in FireFox (version 31) on other browsers (Chrome, Safari, Opera) works perfect. How to fix it ?

Edit (openPopup function):

<script type="text/javascript">
    Polymer('popup-element', {

        domReady : function() {
            var mainThis = this;
            $(this.$.popup).on('click','.closebutton', function(e){
                mainThis.closePopup();
            });
        },
        openPopup : function (){
            $(this.$.popup).show();
            return this;
        },
        closePopup : function (){
            $(this.$.popup).hide();
            return this;
        }
    });

</script>

ANSWER

Ok, now I can see. I had the same problem. I have solved it like this:
Instead of:

$(this.$.popup).show();

Try this:

this.$.popup.style.display = "block";

It seems, it is impossible to use jQuery in polymer element javascript function when you execute it from another polymer element (in firefox only!). Please somebody smarter than me to improve this answer :)

[arv]

getDefaultComputedStyle was just added to the shadow dom polyfill.