1 files changed, 2 insertions, 5 deletions
diff --git a/web-ui/app/js/sandbox.js b/web-ui/app/js/sandbox.js
index 63ce94b2..33b16ea4 100644
--- a/web-ui/app/js/sandbox.js
+++ b/web-ui/app/js/sandbox.js
@@ -1,14 +1,11 @@
 (function () {
   'use strict';
 
-  window.addEventListener('message', function(e) {
-    var mainWindow = e.source;
-    mainWindow.postMessage('data ok', e.origin);
-  });
-
   window.onmessage = function (e) {
     if (e.data.html) {
       document.body.innerHTML = e.data.html;
+      var mainWindow = e.source;
+      mainWindow.postMessage('data ok', e.origin);
     }
   };
 })();