Fix #6893
Fix #9268

* Add local followers page to admin account UI

For moderation, I often find myself wondering who, locally, is following
a remote user. Currently, to see this, I have to go back to the web UI,
paste in their full handle, click their profile, and go to the
"Followers" tab (plus, this information is incidental, and if mastodon
ever decides to resolve all of the follower information, there will be
no place local followers are shown). This PR adds a new page which is
accessible via the "following" count on the admin's account view
page, which shows the local followers. (It has filter parameters for
account location to indicate that only local followers are shown, and
leave room for expansion if mastodon ever decides to store the entire
remote follow list).

* Normalize en.yml

Fix #9606

Fix regression from 3c033c4352

* Add REST API for creating an account

The method is available to apps with a token obtained via the client
credentials grant. It creates a user and account records, as well as
an access token for the app that initiated the request. The user is
unconfirmed, and an e-mail is sent as usual.

The method returns the access token, which the app should save for
later. The REST API is not available to users with unconfirmed
accounts, so the app must be smart to wait for the user to click a
link in their e-mail inbox.

The method is rate-limited by IP to 5 requests per 30 minutes.

* Redirect users back to app from confirmation if they were created with an app

* Add tests

* Return 403 on the method if registrations are not open

* Require agreement param to be true in the API when creating an account

To better align with the list of hashtags

* Add moderation warnings

Replace individual routes for disabling, silencing, and suspending
a user, as well as the report update route, with a unified account
action controller that allows you to select an action (none,
disable, silence, suspend) as well as whether it should generate an
e-mail notification with optional custom text. That notification,
with the optional custom text, is saved as a warning.

Additionally, there are warning presets you can configure to save
time when performing the above.

* Use Account#local_username_and_domain

Fix #7087

The same data is available over the ActivityPub outbox, RSS, and Atom, so
there is little benefit to keeping it limited in this method.

* Move #set_user to Admin::BaseController

* Rename Admin::TwoFactorAuthenticationsController

from `#set_user` to `#set_target_user` .

* Remove "most popular" tab from profile directory, add responsive design

* Remove unused translations

Define `Settings::BaseController#set_body_classes` so that sub classes
inherit `Settings::BaseController` don't need to define
`#set_body_classes` agein.

* Fix markup in admin/accounts/:id table for avatar

* Add admin ability to remove an user's header image

* Add instance-wide setting to disable profile directory

Fixes #9496

When the profile directory is disabled:
- The “discoverable” setting is hidden from users
- The “profile directory” link is not shown on public pages
- /explore returns 404

* Move Setting.profile_directory check to a before_action filter

* Add specs for ActivityPub::CollectionsController#show

* Raise ActiveRecord::RecordNotFound

Raising ActiveRecord::NotFound raises NameError: uninitialized constant
ActiveRecord::NotFound.

* Add setting to not aggregate reblogs

Fixes #9222

* Handle cases where user is nil in add_to_home and add_to_list

* Add hint for setting_aggregate_reblogs option

* Reword setting_aggregate_reblogs label

Fix #5578

* Add test that should currently fail

* Fix depth computation (will still fail if statuses have been filtered out)

* Fix handling of broken threads

* Improve overview of accounts in admin UI

- Display suspended status, role, last activity and IP prominently
- Default to showing local accounts
- Default to not showing suspended accounts

* Remove unused strings

* Fix tests

* Allow filtering accounts by IP mask

* Reduce connect timeout from 10s to 1s

* Limit failing signature verifications per source IP

* Eliminate extra accounts select query from FollowService

* Optimistically update follow state in web UI and hide loading bar

Fix #6205

* Asynchronize NotifyService in FollowService

And fix failing test

* Skip Webfinger resolve routine when called from FollowService if possible

If an account is ActivityPub, then webfinger re-resolving is not necessary
when called from FollowService. Improve options of ResolveAccountService

* Nascent tag menu on frontend

* Hook up frontend to search

* Tag intersection backend first pass

* Update yarnlock

* WIP

* Fix for tags not searching correctly

* Make radio buttons function

* Simplify radio buttons with modeOption

* Better naming

* Rearrange options

* Add all/any/none functionality on backend

* Small PR cleanup

* Move to service from scope

* Small cleanup, add proper service tests

* Don't use send with user input :D

* Set appropriate column header

* Handle auto updating timeline

* Fix up toggle function

* Use tag value correctly

* A bit more correct to use 'self' rather than 'all' in status scope

* Fix some style issues

* Fix more code style issues

* Style select dropdown more better

* Only use to_id'ed value to ensure no SQL injection

* Revamp frontend to allow for multiple selects

* Update backend / col header to account for more flexible tagging

* Update brakeman ignore

* Codeclimate suggestions

* Fix presenter tag_url

* Implement initial PR feedback

* Handle additional tag streaming

* CodeClimate tweak

This reverts commit 10680f93e7.

* Include preview cards in status entity in REST API

* Display preview card in-stream

* Improve in-stream display of preview cards

Fix #9091

* Add "disable" button to report screen

* i18n-tasks remove-unused

* Downcase signed_headers string before building the signed string

The HTTP Signatures draft does not mandate the “headers” field to be downcased,
but mandates the header field names to be downcased in the signed string, which
means that prior to this patch, Mastodon could fail to process signatures from
some compliant clients. It also means that it would not actually check the
Digest of non-compliant clients that wouldn't use a lowercased Digest field
name.

Thankfully, I don't know of any such client.

* Revert "Remove dead code (#8919)"

This reverts commit a00ce8c92c.

* Restore time window checking, change it to 12 hours

By checking the Date header, we can prevent replaying old vulnerable
signatures. The focus is to prevent replaying old vulnerable requests
from software that has been fixed in the meantime, so a somewhat long
window should be fine and accounts for timezone misconfiguration.

* Escape users' URLs when formatting them

Fixes possible HTML injection

* Escape all string interpolations in Formatter class

Slightly improve performance by reducing class allocations
from repeated Formatter#encode calls

* Fix code style issues

* Set CSP rules in RoR's configuration

* Override CSP setting in the embed controller to allow frames

SignatureVerification#matches_time_window? is not called anywhere.

* 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

* Allow min_id pagination in Feed#get

* Add min_id pagination to home and list timeline APIs

* Add min_id pagination to account statuses, public and tag APIs

* Remove unused stub in reports API

* Use min_id pagination in notifications, favourites, and fix order

* Fix HomeFeed#from_database not using paginate_by_id