diff -r 7d1e60244561 -r 4d2ab365699e mercurial/configitems.py
--- a/mercurial/configitems.py	Fri Oct 15 03:28:28 2021 +0200
+++ b/mercurial/configitems.py	Fri Oct 15 03:49:05 2021 +0200
@@ -207,11 +207,6 @@
     b'pushing',
     default=list,
 )
-coreconfigitem(
-    b'bookmarks',
-    b'mirror',
-    default=False,
-)
 # bundle.mainreporoot: internal hack for bundlerepo
 coreconfigitem(
     b'bundle',