--- a/mercurial/configitems.py	Wed Jul 18 09:49:34 2018 -0700
+++ b/mercurial/configitems.py	Tue Jul 10 17:01:06 2018 +0530
@@ -1093,6 +1093,9 @@
 coreconfigitem('ui', 'graphnodetemplate',
     default=None,
 )
+coreconfigitem('ui', 'history-editing-backup',
+    default=True,
+)
 coreconfigitem('ui', 'interactive',
     default=None,
 )