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

Conflicts:
- app/controllers/auth/sessions_controller.rb
  Minor conflict due to glitch-soc's theming code

db/migrate/20190917213523_add_remember_token_index.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddRememberTokenIndex < ActiveRecord::Migration[5.2]
+  disable_ddl_transaction!
+
+  def change
+    add_index :users, :remember_token, algorithm: :concurrently, unique: true
+  end
+end