Display.template.php
Pesquisar por
<a href="', $scripturl, '?action=post;msg=', $message['id'], ';topic=', $context['current_topic'], '.', $context['start'], ';sesc=', $context['session_id'], '">', ($settings['use_image_buttons'] ? '<img src="' . $settings['images_url'] . '/' . $context['user']['language'] . '/modify.gif" alt="' . $txt[66] . '" border="0" />' : $txt[17]), '</a>';
Adicione por baixo:
echo '
<a href="#top">' . ($settings['use_image_buttons'] ? '<img src="' . $settings['images_url'] . '/' . $context['user']['language'] . '/go_up.gif" alt="' . $txt['topbottom4'] . '" border="0" align="top" />' : $txt['topbottom4']) . '</a>';