--- a/mercurial/configitems.py	Wed Oct 11 03:41:48 2017 +0200
+++ b/mercurial/configitems.py	Wed Oct 11 03:45:14 2017 +0200
@@ -383,6 +383,9 @@
 coreconfigitem('pager', 'ignore',
     default=list,
 )
+coreconfigitem('pager', 'pager',
+    default=dynamicdefault,
+)
 coreconfigitem('patch', 'eol',
     default='strict',
 )