Fix class name for icon

src/templates/chatroom_features.html

@@ -27,7 +27,7 @@
 <li class="feature" title="{{{ o.tt_temporary }}}"><span class="fa fa-snowflake-o"></span>{{{ o.label_temporary }}}</li>
 {[ } ]}
 {[ if (o.nonanonymous) { ]}
-<li class="feature" title="{{{ o.tt_nonanonymous }}}"><span class="fa fa-idcard-dark"></span>{{{ o.label_nonanonymous }}}</li>
+<li class="feature" title="{{{ o.tt_nonanonymous }}}"><span class="fa fa-id-card"></span>{{{ o.label_nonanonymous }}}</li>
 {[ } ]}
 {[ if (o.semianonymous) { ]}
 <li class="feature" title="{{{ o.tt_semianonymous }}}"><span class="fa fa-user-secret"></span>{{{ o.label_semianonymous }}}</li>