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/application.html.haml

@@ -44,7 +44,7 @@
     = render partial: 'layouts/theme', object: @core
     = render partial: 'layouts/theme', object: @theme
 
-    = stylesheet_link_tag custom_css_path, host: request.host, media: 'all'
+    = stylesheet_link_tag custom_css_path, skip_pipeline: true, host: root_url, media: 'all'
 
   %body{ class: body_classes }
     = content_for?(:content) ? yield(:content) : yield