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.
