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

Conflicts:
- `app/serializers/rest/account_serializer.rb`:
  Upstream added code too close to glitch-soc-specific followers-hiding code.
  Ported upstream changes.

app/lib/feed_manager.rb

@@ -11,6 +11,10 @@ class FeedManager
   # Must be <= MAX_ITEMS or the tracking sets will grow forever
   REBLOG_FALLOFF = 40
 
+  def with_active_accounts(&block)
+    Account.joins(:user).where('users.current_sign_in_at > ?', User::ACTIVE_DURATION.ago).find_each(&block)
+  end
+
   def key(type, id, subtype = nil)
     return "feed:#{type}:#{id}" unless subtype