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

Conflicts:
- `app/javascript/mastodon/locales/ja.json`:
  Upstream change too close to a glitch-soc-specific string.
  The glitch-soc-specific string should not have been in this file, so it
  has been moved to `app/javascript/flavours/glitch/locales/ja.js`.
- `app/javascript/packs/public.js`:
  Upstream refactored a part, that as usual is split and duplicated in various
  pack files. Updated those pack files accordingly.
- `app/views/layouts/application.html.haml`:
  Upstream fixed custom.css path in a different way than we did, went with
  upstream's change.

app/views/layouts/admin.html.haml

@@ -14,8 +14,9 @@
               = link_to root_path do
                 = logo_as_symbol(:wordmark)
 
-            = link_to '#', class: 'sidebar__toggle__icon' do
+            = link_to '#', class: 'sidebar__toggle__icon', 'aria-label': t('navigation.toggle_menu'), 'aria-expanded': 'false' do
               = fa_icon 'bars'
+              = fa_icon 'times'
 
           = render_navigation