diff --git a/index.html b/index.html
index 0589ac7..7bd204e 100644
--- a/index.html
+++ b/index.html
@@ -42,6 +42,7 @@
   <body class='web'>
     <script>
       'use strict';
+      function Listener(){}
       const dialog = null;
       DOTGRID.install(document.body);
       DOTGRID.start();
