Twitter @anywhere Permission denied to get property Window.jQuery from <https://api.twitter.com> error

Question

I'm just trying add a twitter's tweet box but I'm getting the following error in Firefox:

"Permission denied to get property Window.jQuery from https://api.twitter.com"

It works fine for me in Chrome.

All I have on the page is the code snippet from Twitter's api tutorial which is:

<div id="tbox"></div>
<script type="text/javascript">
  twttr.anywhere(function (T) {
    T("#tbox").tweetBox();
  });

</script>

and twitter's js in the header