Features
--------

- Python 3.5 and 3.6 support is now in beta.
([\#3576](#3576))
- Implement `event_format` filter param in `/sync`
([\#3790](#3790))
- Add synapse_admin_mau:registered_reserved_users metric to expose
number of real reaserved users
([\#3846](#3846))

Bugfixes
--------

- Remove connection ID for replication prometheus metrics, as it creates
a large number of new series.
([\#3788](#3788))
- guest users should not be part of mau total
([\#3800](#3800))
- Bump dependency on pyopenssl 16.x, to avoid incompatibility with
recent Twisted.
([\#3804](#3804))
- Fix existing room tags not coming down sync when joining a room
([\#3810](#3810))
- Fix jwt import check
([\#3824](#3824))
- fix VOIP crashes under Python 3 (#3821)
([\#3835](#3835))
- Fix manhole so that it works with latest openssh clients
([\#3841](#3841))
- Fix outbound requests occasionally wedging, which can result in
federation breaking between servers.
([\#3845](#3845))
- Show heroes if room name/canonical alias has been deleted
([\#3851](#3851))
- Fix handling of redacted events from federation
([\#3859](#3859))
-  ([\#3874](#3874))
- Mitigate outbound federation randomly becoming wedged
([\#3875](#3875))

Internal Changes
----------------

- CircleCI tests now run on the potential merge of a PR.
([\#3704](#3704))
- http/ is now ported to Python 3.
([\#3771](#3771))
- Improve human readable error messages for threepid
registration/account update
([\#3789](#3789))
- Make /sync slightly faster by avoiding needless copies
([\#3795](#3795))
- handlers/ is now ported to Python 3.
([\#3803](#3803))
- Limit the number of PDUs/EDUs per federation transaction
([\#3805](#3805))
- Only start postgres instance for postgres tests on Travis CI
([\#3806](#3806))
- tests/ is now ported to Python 3.
([\#3808](#3808))
- crypto/ is now ported to Python 3.
([\#3822](#3822))
- rest/ is now ported to Python 3.
([\#3823](#3823))
- add some logging for the keyring queue
([\#3826](#3826))
- speed up lazy loading by 2-3x
([\#3827](#3827))
- Improved Dockerfile to remove build requirements after building
reducing the image size.
([\#3834](#3834))
- Disable lazy loading for incremental syncs for now
([\#3840](#3840))
- federation/ is now ported to Python 3.
([\#3847](#3847))
- Log when we retry outbound requests
([\#3853](#3853))
- Removed some excess logging messages.
([\#3855](#3855))
- Speed up purge history for rooms that have been previously purged
([\#3856](#3856))
- Refactor some HTTP timeout code.
([\#3857](#3857))
- Fix running merged builds on CircleCI
([\#3858](#3858))
- Fix typo in replication stream exception.
([\#3860](#3860))
- Add in flight real time metrics for Measure blocks
([\#3871](#3871))
- Disable buffering and automatic retrying in treq requests to prevent
timeouts. ([\#3872](#3872))
- mention jemalloc in the README
([\#3877](#3877))
- Remove unmaintained "nuke-room-from-db.sh" script
([\#3888](#3888))