1 files changed, 9 insertions, 1 deletions
diff --git a/js/app.js b/js/app.js
index 0d91c84..5898f5c 100644
--- a/js/app.js
+++ b/js/app.js
@@ -82,7 +82,15 @@ function bind () {
   })
   
   window.onbeforeunload = function() {
-    if (changed) return "You have edited this drawing."
+    if (changed && !in_iframe()) return "You have edited this drawing."
+  }
+
+  function in_iframe () {
+    try {
+      return window.self !== window.top;
+    } catch (e) {
+      return true;
+    }
   }
 }