diff --git a/js/h5p.js b/js/h5p.js
index 0d5af92e..a28c4cd7 100644
--- a/js/h5p.js
+++ b/js/h5p.js
@@ -1435,7 +1435,9 @@ H5P.isObjectEqual = function (aObject, bObject, aStack, bStack) {
   }
 
   if(aObject === null || bObject === null) {
-    return false;
+    if(aObject !== bObject) {
+      return false;
+    }
   }
 
   if(aObject !== aObject) {