diff -r d5498db5f86a -r a24f4638d6c1 mercurial/wireprotoserver.py
--- a/mercurial/wireprotoserver.py	Sun Sep 30 03:42:35 2018 +0530
+++ b/mercurial/wireprotoserver.py	Sun Sep 30 03:45:51 2018 +0530
@@ -39,6 +39,7 @@
 HGERRTYPE = 'application/hg-error'
 
 NARROWCAP = 'exp-narrow-1'
+ELLIPSESCAP = 'exp-ellipses-1'
 
 SSHV1 = wireprototypes.SSHV1
 SSHV2 = wireprototypes.SSHV2