Based on https://gitlab.com/muttmua/mutt/-/commit/9204b24e99767ae06b5df25eca55c028d702528b
This patch disable enforcing of ssl
diff -ur mutt-2.0.2/doc/manual.xml.head mutt_patch/doc/manual.xml.head
--- mutt-2.0.2/doc/manual.xml.head	2020-11-07 21:30:03.000000000 +0100
+++ mutt_patch/doc/manual.xml.head	2021-01-27 20:21:05.964647359 +0100
@@ -9104,7 +9104,7 @@
   <para>
     When connecting through a <link linkend="tunnel">$tunnel</link>
     and <link linkend="tunnel-is-secure">$tunnel_is_secure</link> is
-    set (the default), Mutt will assume the connection to the server
+    set (Not the default!), Mutt will assume the connection to the server
     through the pipe is already secured.  Mutt will ignore <link
     linkend="ssl-starttls">$ssl_starttls</link> and <link
     linkend="ssl-force-tls">$ssl_force_tls</link>, behaving as if TLS
diff -ur mutt-2.0.2/init.h mutt_patch/init.h
--- mutt-2.0.2/init.h	2020-11-20 02:28:59.000000000 +0100
+++ mutt_patch/init.h	2021-01-27 20:20:09.696052996 +0100
@@ -4021,7 +4021,7 @@
   ** The file containing a client certificate and its associated private
   ** key.
   */
-  { "ssl_force_tls",		DT_BOOL, R_NONE, {.l=OPTSSLFORCETLS}, {.l=1} },
+  { "ssl_force_tls",		DT_BOOL, R_NONE, {.l=OPTSSLFORCETLS}, {.l=0} },
   /*
   ** .pp
   ** If this variable is \fIset\fP, Mutt will require that all connections