Merge branch 'master' into glitch-soc/merge-upstream

Conflicts:
	app/controllers/accounts_controller.rb
	app/javascript/mastodon/locales/pl.json
	app/views/about/more.html.haml

Conflicts in `accounts_controller.rb` resolved by taking upstream's
version + our `use_pack`.

Conflicts in `pl.json` resolved by taking upstream's changes.

Conflicts in `aboute/more.html.haml` resolved by taking upstream's changes.

spec/models/account_pin_spec.rb

@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe AccountPin, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end