Use username for irc nick

sections/chat/index.php

 <?
   } else {
     $nick = $LoggedUser['Username'];
-    $nick = preg_replace('/[^a-zA-Z0-9\[\]\\`\^\{\}\|_]/', '', $nick);
     if (strlen($nick) == 0) {
       $nick = SITE_NAME.'Guest????';
     } else {
     <div style="padding: 0px 10px 10px 20px;">
       <p>If you have an IRC client, refer to <a href="wiki.php?action=article&amp;name=IRC">this wiki article</a> for information on how to connect.</p>
     </div>
-    <iframe src="<?echo 'https://chat.'.SITE_DOMAIN?>" width="100%" height="600" style="border:0;">
+    <iframe src="<?echo 'https://chat.'.SITE_DOMAIN.'?nick='.$nick?>" width="100%" height="600" style="border:0;">
     </iframe>
   </div>
 </div>