--- a/mercurial/configitems.py	Mon Jan 23 17:21:14 2023 +0100
+++ b/mercurial/configitems.py	Mon Jan 23 18:52:05 2023 +0100
@@ -48,10 +48,12 @@
         generic=False,
         priority=0,
         experimental=False,
+        documentation="",
     ):
         self.section = section
         self.name = name
         self.default = default
+        self.documentation = documentation
         self.alias = list(alias)
         self.generic = generic
         self.priority = priority