--- a/mercurial/commands.py	Mon Mar 06 03:26:30 2017 -0800
+++ b/mercurial/commands.py	Mon Mar 06 03:27:24 2017 -0800
@@ -1796,7 +1796,8 @@
 
         editor = ui.geteditor()
         ui.system("%s \"%s\"" % (editor, f),
-                  onerr=error.Abort, errprefix=_("edit failed"))
+                  onerr=error.Abort, errprefix=_("edit failed"),
+                  blockedtag='config_edit')
         return
     ui.pager('config')
     fm = ui.formatter('config', opts)