Release announcements

Zulip Server 4.6 bug fix release

Tim Abbott 2 min read

We released Zulip Server 4.6 today! This is a bug fix release, containing a few dozen cherry-picked changes since Zulip Server 4.5.

What’s new

This release fixes the following issues:

  • Documented official support for Debian 11 Bullseye, now that it is officially released by Debian upstream.
  • Fixed installation on Debian 10 Buster. Upstream infrastructure had broken the Python virtualenv tool on this platform, which we’ve worked around for this release.
  • Zulip releases are now distributed from, replacing the old server.
  • Added support for LDAP synchronization of the is_realm_owner and is_moderator flags.
  • upgrade-zulip-from-git now uses git fetch --prune; this ensures upgrade-zulip-from-git master with return an error rather than using a stale cached version of the master branch, which was renamed to main this month.
  • Added a new reset_authentication_attempt_count management command to allow sysadmins to manually reset authentication rate limits.
  • Fixed a bug that caused the upgrade-postgresql tool to incorrectly remove supervisord configuration for process-fts-updates.
  • Fixed a rare migration bug when upgrading from Zulip versions 2.1 and older.
  • Fixed a subtle bug where the left sidebar would show both old and new names for some topics that had been renamed.
  • Fixed incoming email gateway support for configurations with the http_only setting enabled.
  • Fixed issues where the Slack-compatible interface outgoing webhook variant had a different format from Slack’s documented interface.
  • The installation and upgrade documentations now show the latest release’s version number.
  • Backported many improvements to the ReadTheDocs documentation.
  • Updated translation data from Transifex.


We recommend that all installations upgrade to this new release. See the upgrade instructions in the Zulip documentation. If you need help, best-effort support is available in #production help in the Zulip developer community.


We love feedback from the Zulip user community. Here are a few ways you can participate: