+JH/21 The smtp transport option "hosts_noproxy_tls" is now unset by default.
+ A single TCP connection by a client will now hold a TLS connection open
+ for multiple message deliveries, by default. Previoud the default was to
+ not do so.
+
+JH/22 The smtp transport option "hosts_try_dane" now enables all hosts by
+ default. If built with the facility, DANE will be used. The facility
+ SUPPORT_DANE is now enabled in the prototype build Makefile "EDITME".
+
+JH/23 The build default is now for TLS to be included; the SUPPORT_TLS define
+ is replaced with DISABLE_TLS. Either USE_GNUTLS or (the new) USE_OPENSSL
+ must be defined and you must still, unless you define DISABLE_TLS, manage
+ the the include-dir and library-file requirements that go with that
+ choice. Non-TLS builds are still supported.
+
+JH/24 Fix duplicated logging of peer name/address, on a transport connection-
+ reject under TFO.
+
+JH/25 The smtp transport option "hosts_try_fastopen" now enables all hosts by
+ default. If the platform supports and has the facility enabled, it will
+ be requested on all coneections.
+
+JH/26 The PIPE_CONNECT facility is promoted from experimental status and is now
+ controlled by the build-time option SUPPORT_PIPE_CONNECT.
+
+PP/01 Unbreak heimdal_gssapi, broken in 4.92.
+
+JH/27 Bug 2404: Use the main-section configuration option "dsn_from" for
+ success-DSN messages. Previously the From: header was always the default
+ one for these; the option was ignored.
+
+JH/28 Fix the timeout on smtp response to apply to the whole response.
+ Previously it was reset for every read, so a teergrubing peer sending
+ single bytes within the time limit could extend the connection for a
+ long time. Credit to Qualsys Security Advisory Team for the discovery.
+
+JH/29 Fix DSN Final-Recipient: field. Previously it was the post-routing
+ delivery address, which leaked information of the results of local
+ forwarding. Change to the original envelope recipient address, per
+ standards.
+
+JH/30 Bug 2411: Fix DSN generation when RFC 3461 failure notification is
+ requested. Previously not bounce was generated and a log entry of
+ error ignored was made.
+
+JH/31 Avoid re-expansion in ${sort } expansion. (CVE-2019-13917)
+
+JH/32 Introduce a general tainting mechanism for values read from the input
+ channel, and values derived from them. Refuse to expand any tainted
+ values, to catch one form of exploit.
+
+JH/33 Bug 2413: Fix dkim_strict option. Previously the expansion result
+ was unused and the unexpanded text used for the test. Found and
+ fixed by Ruben Jenster.
+
+JH/34 Fix crash after TLS shutdown. When the TCP/SMTP channel was left open,
+ an attempt to use a TLS library read routine dereffed a nul pointer,
+ causing a segfault.
+
+JH/35 Bug 2409: filter out-of-spec chars from callout response before using
+ them in our smtp response.
+
+JH/36 Have the general router option retry_use_local_part default to true when
+ any of the restrictive preconditions are set (to anything). Previously it
+ was only for check_local user. The change removes one item of manual
+ configuration which is required for proper retries when a remote router
+ handles a subset of addresses for a domain.
+
+JH/37 Appendfile: when evaluating quota use (non-quota_size_regex) take the file
+ link count into consideration.
+
+HS/04 Fix handling of very log lines in -H files. If a -<key> <value> line
+ caused the extension of big_buffer, the following lines were ignored.
+
+JH/38 Bug 1395: Teach the DNS negative-cache about TTL value from the SOA in
+ accordance with RFC 2308. Previously there was no expiry, so a longlived
+ receive process (eg. due to ACL delays) versus a short SOA value could
+ surprise.
+
+HS/05 Handle trailing backslash gracefully. (CVE-2019-15846)
+
+JH/39 Promote DMARC support to mainline.
+
+JH/40 Bug 2452: Add a References: header to DSNs.
+
+JH/41 With GnuTLS 3.6.0 (and later) do not attempt to manage Diffie-Hellman
+ parameters. The relevant library call is documented as "Deprecated: This
+ function is unnecessary and discouraged on GnuTLS 3.6.0 or later. Since
+ 3.6.0, DH parameters are negotiated following RFC7919."
+
+HS/06 Change the default of dnssec_request_domains to "*"
+
+JH/42 Bug 2545: Fix CHUNKING for all RCPT commands rejected. Previously we
+ carried on and emitted a BDAT command, even when PIPELINING was not
+ active.
+
+JH/43 Bug 2465: Fix taint-handling in dsearch lookup. Previously a nontainted
+ buffer was used for the filename, resulting in a trap when tainted
+ arguments (eg. $domain) were used.
+
+JH/44 With OpenSSL 1.1.1 (onwards) disable renegotiation for TLS1.2 and below;
+ recommended to avoid a possible server-load attack. The feature can be
+ re-enabled via the openssl_options main cofiguration option.
+
+JH/45 local_scan API: documented the current smtp_printf() call. This changed
+ for version 4.90 - adding a "more data" boolean to the arguments.
+ Bumped the ABI version number also, this having been missed previously;
+ release versions 4.90 to 4.92.3 inclusive were effectively broken in
+ respect of usage of smtp_printf() by either local_scan code or libraries
+ accessed via the ${dlfunc } expansion item. Both will need coding
+ adjustment for any calls to smtp_printf() to match the new function
+ signature; a FALSE value for the new argument is always safe.
+