diff -r 84d98fa814a8 -r 5cd2d91eeebd mercurial/chgserver.py
--- a/mercurial/chgserver.py	Mon Feb 10 15:52:52 2020 -0800
+++ b/mercurial/chgserver.py	Tue Feb 11 19:53:56 2020 +0900
@@ -83,6 +83,7 @@
     b'eol',  # uses setconfig('eol', ...)
     b'extdiff',  # uisetup will register new commands
     b'extensions',
+    b'schemes',  # extsetup will update global hg.schemes
 ]
 
 _configsectionitems = [