Update:
I’ve narrowed the problem to be associated with LiveZilla chat. When I remove the code from the footer.php <body> the drop down works.
below is the code in question:
<!-- LiveZilla Chat Button Link Code (ALWAYS PLACE IN BODY ELEMENT) -->
<!-- LiveZilla Tracking Code (ALWAYS PLACE IN BODY ELEMENT) -->
<div id="livezilla_tracking" style="display:none"></div><script type="text/javascript">
var script = document.createElement("script");
script.async=true;script.type="text/javascript";
var src = "mysite.foo="+Math.random();
setTimeout("script.src=src;document.getElementById('livezilla_tracking').appendChild(script)",1);
</script>
<noscript>
<img src="mysite.foo" width="0" height="0" style="visibility:hidden;" alt="">
</noscript>
<!-- https://www.LiveZilla.net Tracking Code -->
<div style="display:none;">
<a href="javascript:void(window.open('mysite.foo','','width=610,height=760,left=0,top=0,resizable=yes,menubar=no,location=no,status=yes,scrollbars=yes'))" class="lz_fl">
<img id="chat_button_image" src="mysite.foo" width="34" height="166" style="border:0px;" alt="LiveZilla Live Chat Software"></a>
</div>
<!-- https://www.LiveZilla.net Chat Button Link Code -->
Ideas?