The condition introduced by #9998 was wrong, serializing boosts
that weren't self-boosts, and not serializing self-boosts.

* Fetch up to 5 replies when discovering a new remote status

This is used for resolving threads downwards. The originating
server must add a “replies” attributes with such replies for it to
be useful.

* Add some tests for ActivityPub::FetchRepliesWorker

* Add specs for ActivityPub::FetchRepliesService

* Serialize up to 5 public self-replies for ActivityPub notes

* Add specs for ActivityPub::NoteSerializer

* Move exponential backoff logic to a worker concern

* Fetch first page of paginated collections when fetching thread replies

* Add specs for paginated collections in replies

* Move Note replies serialization to a first CollectionPage

The collection isn't actually paginable yet as it has no id nor
a `next` field. This may come in another PR.

* Use pluck(:uri) instead of map(&:uri) to improve performances

* Fix fetching replies when they are in a CollectionPage

Fix #8785

Fix #9350

* When self-boosting, embed original toot into Announce serialization

* Process unknown self-boosts from Announce object if it is more than an URI

* Add some self-boost specs

* Only serialize private toots in self-Announces

* Make storing and displaying application used to toot opt-in

* Revert to storing application info, and display it to the author via API

* Update manifest.json for new Web Share Target API.

* fix code formatting

This reverts commit bb96a74637.

The database column and API param are called in_reply_to_id, not
in_reply_to_status_id, so it makes no sense to encode it that way

Fix #340

* Allow to show a specific status in the admin interface

* Let the front-end know the current account is a moderator

* Add admin links to status and account menus

If the current logged-in user is an admin, add quick links to the admin
interface in account and toot dropdown menu. Suggestion by @ashkitten

* Use @statuses.first instead of @statuses[0]

This reverts commit 0f938ff29c.

This is only available if the instance-wide setting isn't set and allows
people to hide their own followers count. This does not hide others' to
them.

* Include preview cards in status entity in REST API

* Display preview card in-stream

* Improve in-stream display of preview cards

* Add silent column to mentions

* Save silent mentions in ActivityPub Create handler and optimize it

Move networking calls out of the database transaction

* Add "limited" visibility level masked as "private" in the API

Unlike DMs, limited statuses are pushed into home feeds. The access
control rules between direct and limited statuses is almost the same,
except for counter and conversation logic

* Ensure silent column is non-null, add spec

* Ensure filters don't check silent mentions for blocks/mutes

As those are "this person is also allowed to see" rather than "this
person is involved", therefore does not warrant filtering

* Clean up code

* Use Status#active_mentions to limit returned mentions

* Fix code style issues

* Use Status#active_mentions in Notification

And remove stream_entry eager-loading from Notification

Follow-up to #8766

* Add conversations API

* Add web UI for conversations

* Add test for conversations API

* Add tests for ConversationAccount

* Improve web UI

* Rename ConversationAccount to AccountConversation

* Remove conversations on block and mute

* Change last_status_id to be a denormalization of status_ids

* Add optimistic locking

* Verify link ownership with rel="me"

* Add explanation about verification to UI

* Perform link verifications

* Add click-to-copy widget for verification HTML

* Redesign edit profile page

* Redesign forms

* Improve responsive design of settings pages

* Restore landing page sign-up form

* Fix typo

* Support <link> tags, add spec

* Fix links not being verified on first discovery and passive updates

* Only display web push notifications after API call (fixes #7902)

* Decode then truncate instead of truncating then decoding in webpush serializer

When serializing an ActivityPub actor, Mastodon checks for the existence
of the avatar/header files. This is not necessary, only check if avatar/header
is set.

fd8bf49d38/README.md (checking-a-file-exists)

* Add remote interaction dialog for toots

* Change AuthorizeFollow into AuthorizeInteraction, support statuses

* Update brakeman.ignore

* Adjust how interaction buttons are display on public pages

* Fix tests

* Move status counters to separate table, count replies

* Migration to remove old counter columns from statuses table

* Fix schema file

Fix #7846

* Add federation relay support

* Add admin UI for managing relays

* Include actor on relay-related activities

* Fix i18n

* Add option to not consider word boundaries when filtering phrases

* Add a few tests for keyword/phrase filtering

* Add keyword filtering

    GET|POST       /api/v1/filters
    GET|PUT|DELETE /api/v1/filters/:id

- Irreversible filters can drop toots from home or notifications
- Other filters can hide toots through the client app
- Filters use a phrase valid in particular contexts, expiration

* Make sure expired filters don't get applied client-side

* Add missing API methods

* Remove "regex filter" from column settings

* Add tests

* Add test for FeedManager

* Add CustomFilter test

* Add UI for managing filters

* Add streaming API event to allow syncing filters

* Fix tests

* Serialize language into ActivityPub JSON

* Only use contentMap if language is present

* Allow selecting default posting language instead of auto-detect

* Enable default language setting in credentials API

* Fix form saving

Fix #7820

- Find friends from Twitter (bridge)
- Invite people (when invites enabled)
- Security (change e-mail/password)
- Developers (create OAuth apps/tokens)