dovecot2: updated to 2.3.20

v2.3.20

+ Add dsync_features=no-header-hashes. When this setting is enabled and
  one dsync side doesn't support mail GUIDs (i.e. imapc), there is no
  fallback to using header hashes. Instead, dsync assumes that all mails
  with identical IMAP UIDs contains the same mail contents. This can
  significantly improve dsync performance with some IMAP servers that
  don't support caching Date/Message-ID headers.
+ lua: HTTP client has more settings now, see
  https://doc.dovecot.org/admin_manual/lua/#dovecot.http.client
+ replicator: "doveadm replicator status" command now outputs when the
  next sync is expected for the user.
- LAYOUT=index: duplicate GUIDs were not cleaned out. Also the list
  recovery was not optimal.
- auth: Assert crash would occur when iterating multiple userdb
  backends.
- director: Logging into director using master user with
  auth_master_user_separator character redirected user to a wrong
  backend, unless master_user_separator setting was also set to the same
  value. Merged these into auth_master_user_separator.
- dsync: Couldn't always fix folder GUID conflicts automatically with
  Maildir format. This resulted in replication repeatedly failing
  with "Remote lost mailbox GUID".
- dsync: Failed to migrate INBOX when using namespace prefix=INBOX/,
  resulting in "Remote lost mailbox GUID" errors.
- dsync: INBOX was created too early with namespace prefix=INBOX/,
  resulting a GUID conflict. This may have been resolved automatically,
  but not always.
- dsync: v2.3.18 regression: Wrong imapc password with dsync caused
  Panic: file lib-event.c: line 506 (event_pop_global):
  assertion failed: (event == current_global_event)
- imapc: Requesting STATUS for a mailbox with imapc and INDEXPVT
  configured did not return correct (private) unseen counts.
- lib-dict: Process would crash when committing data to redis without
  dict proxy.
- lib-mail: Corrupted cached BODYSTRUCTURE caused panic during FETCH.
  Fixes: Panic: file message-part-data.c: line 579 (message_part_is_attachment):
  assertion failed: (data != NULL). v2.3.13 regression.
- lib-storage: mail_attribute_dict with dict-sql failed when it tried to
  lookup empty dict keys.
- lib: ioloop-kqueue was missing include breaking some BSD builds.
- lua-http: Dovecot Lua HTTP client could not resolve DNS names in mail
  processes, because it expected "dns-client" socket to exist in the
  current directory.
- oauth2: Using %{oauth2:name} variables could cause useless
  introspections.
- pop3: Sending POP3 command with ':' character caused an assert-crash.
  v2.3.18 regression.
- replicator: Replication queue had various issues, potentially causing
  replication requests to become stuck.
- stats: Invalid Prometheus label names were created with specific

v0.5.20 of Pigeonhole
* No changes - release done to keep version numbers synced.


(adam)