BBCode only works in single post, not full thread

[kh99]

Try using:

<script type="text/javascript">
        var theonload = window.onload;
        window.onload = function(){
            if (theonload) theonload();
            prettyPrint();
        }
</script>

the part in red is added. The fact that theonload isn't a function is causing an error on the page that doesn't work, but I don't know why it's not causing an error on both pages.