From 141f01b102fb8b1ce38647e56550d00581a80aa0 Mon Sep 17 00:00:00 2001
From: Park Hyunwoo <ez.amiryo@gmail.com>
Date: Thu, 13 Dec 2018 03:38:41 +0900
Subject: [PATCH] Prevent undo error from malformed range

---
 src/js/base/editing/History.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/js/base/editing/History.js b/src/js/base/editing/History.js
index 734fddec6..3faff5e4f 100644
--- a/src/js/base/editing/History.js
+++ b/src/js/base/editing/History.js
@@ -14,7 +14,7 @@ export default class History {
 
     return {
       contents: this.$editable.html(),
-      bookmark: (rng ? rng.bookmark(this.editable) : emptyBookmark),
+      bookmark: ((rng && rng.isOnEditable()) ? rng.bookmark(this.editable) : emptyBookmark),
     };
   }