Mautrix-telegram

Added
* Added built-in custom emoji packs to allow reacting with any standard unicode
emoji from Matrix (note that only premium users can use custom emojis).
* Added infinite backfill using [MSC2716].
* The new system includes a backwards compatibility mechanism which uses the
old method of just sending events to the room. By default, MSC2716 is not
enabled and the legacy method will be used.

Improved
* Redacting reactions on Matrix no longer removes the user's other reactions to
the same message (premium users can have up to 3 reactions per message).
* Changes to default user permissions on Telegram are now bridged.
* Added database index to make reaction polling more efficient
(thanks to [AndrewFerr] in [862]).

Fixed
* Fixed provisioning API not working with URL-encoded parameters.

[MSC2716]: https://github.com/matrix-org/matrix-spec-proposals/pull/2716
[AndrewFerr]: https://github.com/AndrewFerr
[862]: https://github.com/mautrix/telegram/pull/862

Added
* Support for custom emojis in reactions.
* Like other bridges with custom emoji reactions, they're bridged as `mxc://`
URIs, so client support is required to render them properly.

Improved
* The bridge will now poll for reactions to 20 most recent messages when
receiving a read receipt. This works around Telegram's bad protocol that
doesn't notify clients on reactions to other users' messages.
* The docker image now has an option to bypass the startup script by setting
the `MAUTRIX_DIRECT_STARTUP` environment variable. Additionally, it will
refuse to run as a non-root user if that variable is not set (and print an
error message suggesting to either set the variable or use a custom command).
* Moved environment variable overrides for config fields to mautrix-python.
The new system also allows loading JSON values to enable overriding maps like
`login_shared_secret_map`.

Fixed
* `ChatParticipantsForbidden` is handled properly when syncing non-supergroup
info.
* Fixed some bugs with file transfers when using SQLite.
* Fixed error when attempting to log in again after logging out.
* Fixed QR login not working.
* Fixed error syncing chats if bridging a message had previously been
interrupted.

**N.B.** This release requires a homeserver with Matrix v1.1 support, which
bumps up the minimum homeserver versions to Synapse 1.54 and Dendrite 0.8.7.
Minimum Conduit version remains at 0.4.0.

Added
* Added provisioning API for resolving Telegram identifiers (like usernames).
* Added support for bridging Telegram custom emojis to Matrix.
* Added option to not bridge chats with lots of members.
* Added option to include captions in the same message as the media to
implement [MSC2530]. Sending captions the same way is also supported and
enabled by default.
* Added commands to kick or ban relaybot users from Telegram.
* Added support for Telegram's disappearing messages.
* Added support for bridging forwarded messages as forwards on Telegram.
* Forwarding is not allowed in relay mode as the bot wouldn't be able to
specify who sent the message.
* Matrix doesn't have real forwarding (there's no forwarding metadata), so
only messages bridged from Telegram can be forwarded.
* Double puppeted messages from Telegram currently can't be forwarded without
removing the `fi.mau.double_puppet_source` key from the content.
* If forwarding fails (e.g. due to it being blocked in the source chat), the
bridge will automatically fall back to sending it as a normal new message.
* Added options to make encryption more secure.
* The `encryption` -> `verification_levels` config options can be used to
make the bridge require encrypted messages to come from cross-signed
devices, with trust-on-first-use validation of the cross-signing master
key.
* The `encryption` -> `require` option can be used to make the bridge ignore
any unencrypted messages.
* Key rotation settings can be configured with the `encryption` -> `rotation`
config.

Improved
* Improved handling the bridge user leaving chats on Telegram, and new users
being added on Telegram.
* Improved animated sticker conversion options: added support for animated webp
and added option to convert video stickers (webm) to the specified image
format.
* Audio and video metadata is now bridged properly to Telegram.
* Added database index on Telegram usernames (used when bridging username
-mentions in messages).
* Changed `/login/send_code` provisioning API to return a proper error when the
phone number is not registered on Telegram.
* The same login code can be used for registering an account, but registering
is not currently supported in the provisioning API.
* Removed `plaintext_highlights` config option (the code using it was already
removed in v0.11.0).
* Enabled appservice ephemeral events by default for new installations.
* Existing bridges can turn it on by enabling `ephemeral_events` and disabling
`sync_with_custom_puppets` in the config, then regenerating the registration
file.
* Updated to API layer 144 so that Telegram would send new message types like
premium stickers to the bridge.
* Updated Docker image to Alpine 3.16 and made it smaller.

Fixed
* Fixed command prefix in game and poll messages (thanks to [cynhr] in [804]).

[MSC2530]: https://github.com/matrix-org/matrix-spec-proposals/pull/2530
[cynhr]: https://github.com/cynhr
[804]: https://github.com/mautrix/telegram/pull/804

**N.B.** This release drops support for old homeservers which don't support the
new `/v3` API endpoints. Synapse 1.48+, Dendrite 0.6.5+ and Conduit 0.4.0+ are
supported. Legacy `r0` API support can be temporarily re-enabled with `pip install mautrix==0.16.0`.
However, this option will not be available in future releases.

Added
* Added `list-invite-links` command to list invite links in a chat.
* Added option to use [MSC2246] async media uploads.
* Provisioning API for listing contacts and starting private chats.

Improved
* Dropped Python 3.7 support.
* Telegram->Matrix message formatter will now replace `t.me/c/chatid/messageid`
style links with a link to the bridged Matrix event (in addition to the
previously supported `t.me/username/messageid` links).
* Updated formatting converter to keep newlines in code blocks as `\n` instead
of converting them to `<br/>`.
* Removed `max_document_size` option. The bridge will now fetch the max size
automatically using the media repo config endpoint.
* Removed redundant `msgtype` field in sticker events sent to Matrix.
* Disabled file logging in Docker image by default.
* If you want to enable it, set the `filename` in the file log handler to a
path that is writable, then add `"file"` back to `logging.root.handlers`.
* Reactions are now marked as read when bridging read receipts from Matrix.

Fixed
* Fixed `!tg bridge` throwing error if the parameter is not an integer
* Fixed `!tg bridge` failing if the command had been previously run with an
incorrectly prefixed chat ID (e.g. `!tg bridge -1234567` followed by
`!tg bridge -1001234567`).
* Fixed `bridge_matrix_leave` config option not actually being used correctly.
* Fixed public channel mentions always bridging into a user mention on Matrix
rather than a room mention.
* The bridge will now make room mentions if the portal exists and fall back
to user mentions otherwise.
* Fixed newlines being lost in unformatted forwarded messages.

[MSC2246]: https://github.com/matrix-org/matrix-spec-proposals/pull/2246

**N.B.** This will be the last release to support Python 3.7. Future versions
will require Python 3.8 or higher. In general, the mautrix bridges will only
support the lowest Python version in the latest Debian or Ubuntu LTS.

Added
* Added simple fallback message for live location and venue messages from Telegram.
* Added support for `t.me/+code` style invite links in `!tg join`.
* Added support for showing channel profile when users send messages as a channel.
* Added "user joined Telegram" message when Telegram auto-creates a DM chat for
a new user.

Improved
* Added option for adding a random prefix to relayed user displaynames to help
distinguish them on the Telegram side.
* Improved syncing profile info to room info when using encryption and/or the
`private_chat_profile_meta` config option.
* Removed legacy `community_id` config option.

Fixed
* Fixed newlines disappearing when bridging channel messages with signatures.
* Fixed login throwing an error if a previous login code expired.
* Fixed bug in v0.11.0 that broke `!tg create`.

Added
* Added support for message reactions.
* Added support for spoiler text.

Improved
* Support for voice messages.
* Changed color of blue text from Telegram to be more readable on dark themes.

Fixed
* Fixed syncing contacts throwing an error for new accounts.
* Fixed migrating pre-v0.11 legacy databases if the database schema had been
corrupted (e.g. by using 3rd party tools for SQLite -> Postgres migration).
* Fixed converting animated stickers to webm with >33 FPS.
* Fixed a bug in v0.11.0 that broke mentioning users in groups
(thanks to [dfuchss] in [724]).

[dfuchss]: https://github.com/dfuchss
[724]: https://github.com/mautrix/telegram/pull/724