Merge commit 'b0780cfeeda641645ea65da257a72ec507e71647' into glitch-soc/merge-upstream

Conflicts:
- `app/javascript/mastodon/load_locale.js`:
  The file moved to `app/javascript/mastodon/locales/load_locale.ts`.
  Ported the changes there and deleted `app/javascript/mastodon/load_locale.js`.
- `app/javascript/mastodon/locales/index.js`:
  The file moved to `app/javascript/mastodon/locales/index.ts`.
  Did *not* port the changes as I want to try something a bit different.

spec/helpers/react_component_helper_spec.rb

@@ -33,7 +33,7 @@ describe ReactComponentHelper do
 
     it 'returns a tag with data attributes' do
       expect(parsed_html.div['data-admin-component']).to eq('Name')
-      expect(parsed_html.div['data-props']).to eq('{"locale":"en","one":"two"}')
+      expect(parsed_html.div['data-props']).to eq('{"one":"two"}')
     end
   end