Specifically, this commit:

- changes S::TFA::{Confirmations,RecoveryCodes}Controller to derive from
  S::BaseController, because this gives us the necessary actions and
  packs
- prepends set_pack to Auth::SessionsController's action chain so that
  it takes effect in time for render :two_factor

* Add aria-autocomplete='list' in Textaria

ref: https://www.w3.org/TR/wai-aria-1.1/#aria-autocomplete

* Make detect empty string brefore assign upload description

* Change code elements in keyboard-shortcuts component to kbd

* Update Korean translation

* Translate Korean for javascript

* Add missing translations on simple_form

* Add Slovak translation

* Slovak translation: i18n-normalize

* i18n: (zh-CN) Change `工作人员` (staff) to `管理人员`
Suggested by @Gargron at https://github.com/tootsuite/mastodon/pull/6005#discussion_r156678109

* i18n: (zh-CN) Change `协管` to `监察员`

* i18n: (zh-CN) Fix all "Are you" questions

* i18n: (zh-CN) Various improvements

* i18n: (zh-CN) Final clean-up

* i18n: (zh-CN) Change translation for 500

* i18n: (zh-CN) Remove spaces between time distances

* i18n: (zh-CN) Improve translations

* Last minute Dutch strinfupdate

* Last minute Dutch strings update

* Fixing Weblate output errors

* Fixing Weblate output errors

* Fixing more Weblate rubish

Weblate is also changing some " to ' - I think that is not a problem

* Fixing more weblate stuff

* Fixing

* Update nl.yml

This commit also:

- exposes the local-only emoji so that it can be used in examples
- allows local_only to be set explicitly, i.e. for timeline filtering
  specs

* Fix overflowing emojis on some devices

* Quit visible and add padding

* Adjust empty list timeline message (#5997)

* Adjust empty list timeline message (#5997)

* Add filters to admin UI for custom emojis (#6003) + #6004

* Update fr.yml

* Excahnge the order of spoiler-input and unlocked warning

* Fix trailing whitespace

* Redesign tootbox

* Move counter into compose-form__buttons-wrapper

Change font and remove shadow
Refactor sass codes of compose-form

* Translated using Weblate (Dutch)

Currently translated at 100.0% (522 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/nl/

* Translated using Weblate (French)

Currently translated at 99.8% (521 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/fr/

* Translated using Weblate (Catalan)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/ca/

* Translated using Weblate (Catalan)

Currently translated at 99.4% (519 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/ca/

* Translated using Weblate (Japanese)

Currently translated at 99.4% (519 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/ja/

* Translated using Weblate (Portuguese)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/pt/

* Translated using Weblate (Dutch)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/nl/

* Translated using Weblate (Galician)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/gl/

* Translated using Weblate (Japanese)

Currently translated at 99.6% (520 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/ja/

* Translated using Weblate (Japanese)

Currently translated at 100.0% (56 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/ja/

* Translated using Weblate (Arabic)

Currently translated at 40.0% (209 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/ar/

* Translated using Weblate (Arabic)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/ar/

* Translated using Weblate (Polish)

Currently translated at 99.8% (521 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/pl/

* Added translation using Weblate (Galician)

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 99.0% (517 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/pt_BR/

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/pt_BR/

* Translated using Weblate (Galician)

Currently translated at 100.0% (56 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/gl/

* Added translation using Weblate (Galician)

* Translated using Weblate (Galician)

Currently translated at 100.0% (56 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/gl/

* Translated using Weblate (Galician)

Currently translated at 22.6% (17 of 75 strings)

Translation: Mastodon/Doorkeeper
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/doorkeeper/gl/

* Translated using Weblate (Portuguese)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/pt/

* Translated using Weblate (Portuguese)

Currently translated at 66.0% (37 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/pt/

* Translated using Weblate (Japanese)

Currently translated at 99.6% (520 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/ja/

* Translated using Weblate (Japanese)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/ja/

* Translated using Weblate (Japanese)

Currently translated at 100.0% (43 of 43 strings)

Translation: Mastodon/Devise
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/devise/ja/

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 99.6% (520 of 522 strings)

Translation: Mastodon/Backend
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/backend/pt_BR/

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/pt_BR/

* Translated using Weblate (Arabic)

Currently translated at 100.0% (257 of 257 strings)

Translation: Mastodon/React
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/frontend/ar/

* Translated using Weblate (Arabic)

Currently translated at 48.8% (21 of 43 strings)

Translation: Mastodon/Devise
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/devise/ar/

* Translated using Weblate (Arabic)

Currently translated at 98.2% (55 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/ar/

* Translated using Weblate (Portuguese)

Currently translated at 73.2% (41 of 56 strings)

Translation: Mastodon/Preferences
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/simple_form/pt/

* Translated using Weblate (Portuguese)

Currently translated at 100.0% (43 of 43 strings)

Translation: Mastodon/Devise
Translate-URL: https://weblate.joinmastodon.org/projects/mastodon/devise/pt/

* i18n-tasks normalize && yarn manage:translations

* Restore wrongfully deleted files

* i18n: (zh-CN) Remove spaces in time distances

* i18n: (zh-CN) Update translations for #5997

* i18n: (zh-CN) Add translation for #6004
also change translation of `staff` from `管理员` to `工作人员`

* i18n: (zh-CN) Add translations for #6003

* i18n: (zh-CN) Normalization

* Add staff filter to admin UI for accounts, remove obsolete columns

* Only display OStatus section in admin UI for accounts when OStatus data

* Fix #5952 - NameError (regression from #5762)

* Fix

* Add aria-autocomplete='list' in Textaria

ref: https://www.w3.org/TR/wai-aria-1.1/#aria-autocomplete

* Make detect empty string brefore assign upload description

The preview image would be useful to embed in timeline.

Avoid error when the service returns a mostly valid oembed, but has no
url in it, causing a MethodError: undefined method `url'
for #<OEmbed::Response::Photo:0x000056505def9620>

* Change conditional to avoid nil into string error in sidekiq
When obtaining information about users with mastodon in a different
subdomain, sidekiq was giving out a 'no implicit conversion of nil into String'

* Use presence instead of blank? with ternary.
Following suggestion on PR