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

Conflicts:
- `README.md`:
  Our README.md files are completely different. Discarded upstream changes.
- `app/javascript/core/admin.js`:
  Updating rails-ujs, no real conflict, but a comment to close to changed
  code. Various glitch-soc-only files have been updated to match those changes,
  though.
- `package.json`:
  No real conflict, just an additional dependency in glitch-soc that was too
  close to something updated upstream. Took upstream's changes.

app/models/status.rb

@@ -148,10 +148,12 @@ class Status < ApplicationRecord
       ids += mentions.where(account: Account.local).pluck(:account_id)
       ids += favourites.where(account: Account.local).pluck(:account_id)
       ids += reblogs.where(account: Account.local).pluck(:account_id)
+      ids += bookmarks.where(account: Account.local).pluck(:account_id)
     else
       ids += preloaded.mentions[id] || []
       ids += preloaded.favourites[id] || []
       ids += preloaded.reblogs[id] || []
+      ids += preloaded.bookmarks[id] || []
     end
 
     ids.uniq