noopener on external links

masks/email_conf.html

@@ -25,7 +25,7 @@
 			</tr>
 			<tr>
 				<td colspan="2">
-					<p>[#]lang:email_unsubscribe[#] <a href="[#]unsubscribe_link[#]" target="_blank">[#]lang:email_unsub_btn[#]</a></p>
+					<p>[#]lang:email_unsubscribe[#] <a href="[#]unsubscribe_link[#]" target="_blank" rel="noopener">[#]lang:email_unsub_btn[#]</a></p>
 				</td>
 			</tr>
 		</table>