fix async

config/initializers/devise.rb

@@ -309,4 +309,6 @@ Devise.setup do |config|
   # changed. Defaults to true, so a user is signed in automatically after changing a password.
   # config.sign_in_after_change_password = true
 end
-Devise::Async.backend = :sucker_punch
+Devise::Async.setup do |config|
+  config.enabled = true
+end