Will check it out next week.

/me tried to fix it with http://pastebin.com/9ysSpjgh but was told that is not the proper way to do such things.

Console says source of problem is:

<script type="text/javascript">addOnloadHook(function(){document.getElementById('wpReplyTo14667').focus();});</script>

These scripts should not be inline as mediawiki modules are not available untill the end of the page.

<RoanKattouw> The right way would be to add the following code to codereview.js or its equivalent:
<RoanKattouw> Or wait, we don't have $id on the client side, it'd need to be exported

(before you came in)

Fixed in r83352.

Removed inline scripting and added to core module instead. using the class intead of the $id.