I've implemented a simple example of the Twitter @anywhere api to display user hovercards. The example works great in Internet Explorer and Chrome. However, whenever I the page loads in Firefox I receive the following message in an alert window:

To set up @anywhere, please provide a client ID

Surely if the results are correct in Chrome and IE then everything must be setup correctly?

Here is a simple code block which I've tested recreates the problem in Firefox only:

<script src="http://platform.twitter.com/anywhere.js?id=WMg5kRMlIw807lRTsktnNQ&amp;v=1" type="text/javascript" >
</script>
<script type="text/javascript">
 twttr.anywhere(onAnywhereLoad);
 function onAnywhereLoad(twitter) {
    twitter().hovercards();
 }); 
</script>