The documentation was lacking the needed want-reply field in the initial
global request.
https://github.com/openssh/openssh-portable/pull/218 by dbussink
byte SSH_MSG_GLOBAL_REQUEST
string "hostkeys-00@openssh.com"
+ char 0 /* want-reply */
string[] hostkeys
Upon receiving this message, a client should check which of the
PROTOCOL.mux over a Unix domain socket for communications between a
master instance and later clients.
-$OpenBSD: PROTOCOL,v 1.40 2021/02/18 00:30:17 djm Exp $
+$OpenBSD: PROTOCOL,v 1.41 2021/02/18 02:49:35 djm Exp $