Hi, look the mark in the screenshot.
Thats weird I cant get that error here.
Confirmed here, perhaps the screenshot isn't clear enough but this only occurs on the category pages, not the home page.
This is because the javascript this language variable loads from isn't available on the category pages.
This is the code (from the index template):
<script type="text/javascript">
<!--
lang.no_new_posts = "Forum Contains No New Posts";
lang.click_mark_read = "Click to mark this forum as read";
// -->
</script>
oh sorry, it must be located on my computer. now the question bug away.
Thank you for your bug report.
This bug has been fixed in our internal code repository. Please note that the problem will not be fixed here until these forums are updated.