Replace applicable code blocks with:
// Print the categories and forums
$result = $db->query('SELECT c.id AS cid, c.cat_name, f.id AS fid, f.forum_name, f.forum_desc, f.redirect_url, f.moderators, f.num_topics, f.num_posts, f.last_post, f.last_post_id, f.last_poster, u.id AS uid, t.subject FROM '.$db->prefix.'categories AS c INNER JOIN '.$db->prefix.'forums AS f ON c.id=f.cat_id INNER JOIN '.$db->prefix.'users AS u ON f.last_poster = u.username INNER JOIN '.$db->prefix.'topics AS t ON t.last_post_id = f.last_post_id LEFT JOIN '.$db->prefix.'forum_perms AS fp ON (fp.forum_id=f.id AND fp.group_id='.$pun_user['g_id'].') WHERE fp.read_forum IS NULL OR fp.read_forum=1 ORDER BY c.disp_position, c.id, f.disp_position', true) or error('Unable to fetch category/forum list', __FILE__, __LINE__, $db->error());
// If there is a last_post/last_poster.
if ($cur_forum['last_post'] != '')
$last_post = '<a href="viewtopic.php?pid='.$cur_forum['last_post_id'].'#p'.$cur_forum['last_post_id'].'">'.pun_htmlspecialchars($cur_forum['subject']).'</a> <span class="byuser">'.$lang_common['by'].' <a href="profile.php?id='.$cur_forum['uid'].'">'.pun_htmlspecialchars($cur_forum['last_poster']).'</a></span>';
else
$last_post = ' ';
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