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

Conflicts:
- app/views/admin/settings/edit.html.haml:
  Conflict due to how the theming settings change.

app/services/app_sign_up_service.rb

@@ -18,6 +18,6 @@ class AppSignUpService < BaseService
   private
 
   def allowed_registrations?
-    Setting.open_registrations && !Rails.configuration.x.single_user_mode
+    Setting.registrations_mode != 'none' && !Rails.configuration.x.single_user_mode
   end
 end