This may have been brought up before, but I'm being pestered by a few of my forum members who used to use this on our old phpBB board.
Is this available for the Classic theme?
It is but at the moment you have to add in the link yourself, edit index.template.php in the classic directory and add the link somewhere in the template - it should look like this:
<a href="' . $scripturl . '?action=unread">' . $txt['unread_since_visit'] . '</a>
Just put that whereever you want it to appear. If after doing that you get a parse error change it to this:
echo '
<a href="' . $scripturl . '?action=unread">' . $txt['unread_since_visit'] . '</a>';
Just depends where you try to put it.