* Skip `og` and `meta` tags where the value is empty.
* Fallback to the favicon if there are no other images.
* Ignore tags meant for navigation.

* Update worker docs to remove group endpoints.
* Removes an unused parameter to `ApplicationService`.
* Break dependency between media repo and groups.
* Avoid copying `m.room.related_groups` state events during room upgrades.

Signed-off-by: Nicolas Werner <nicolas.werner@hotmail.de>
Co-authored-by: Brendan Abolivier <github@brendanabolivier.com>

Signed-off-by: Sumner Evans <sumner@beeper.com>

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

Instead of hard-coding strings in many places.

Add an option allowing users to use their password to reauthenticate even though password authentication is disabled. (#12883)

Including handlers, configuration code, appservice support, and
the GroupID construct.

Removes the unstable endpoint as well as a duplicated field
which was modified during stabilization.

* Refactor HTTP response size limits

Rather than passing a separate `max_response_size` down the stack, make it an
attribute of the `parser`.

* Allow bigger responses on `federation/v1/state`

`/state` can return huge responses, so we need to handle that.

Makes it so that groups/communities no longer exist from a user-POV. E.g. we remove:

* All API endpoints (including Client-Server, Server-Server, and admin).
* Documented configuration options (and the experimental flag, which is now unused).
* Special handling during room upgrades.
* The `groups` section of the `/sync` response.

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

Implements the following behind an experimental configuration flag:

* A new push rule kind for mutually related events.
* A new default push rule (`.m.rule.thread_reply`) under an unstable prefix.

This is missing part of MSC3772:

* The `.m.rule.thread_reply_to_me` push rule, this depends on MSC3664 / #11804.

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Update EventContext `get_current_event_ids` and `get_prev_event_ids` to accept state filters and update calls where possible (#12791)

Lay some foundation work to allow workers to only subscribe to some kinds of messages, reducing replication traffic. (#12672)

Refactor `resolve_state_groups_for_events` to not pull out full state when no state resolution happens. (#12775)

Co-authored-by: David Robertson <david.m.robertson1@gmail.com>

The main differences are:
- values with delimiters (such as colons) should be quoted, so always
  quote the origin, since it could contain a colon followed by a port
  number
- should allow more than one space after "X-Matrix"
- quoted values with backslash-escaped characters should be unescaped
- names should be case insensitive

This column is unused as of #12209, so let's stop writing to it.

A minor optimization to avoid unnecessary copying/building
identical dictionaries when filtering private read receipts.

Also clarifies comments and cleans-up some tests.

Signed-off-by: Sean Quah <seanq@element.io>

Parse the `m.relates_to` event content field (which describes relations)
in a single place, this is used during:

* Event persistence.
* Validation of the Client-Server API.
* Fetching bundled aggregations.
* Processing of push rules.

Each of these separately implement the logic and each made slightly
different assumptions about what was valid. Some had minor / potential
bugs.