--- a/config/initializers/new_framework_defaults.rb	Sat Apr 14 04:19:29 2018 +0900
+++ b/config/initializers/new_framework_defaults.rb	Sat Apr 14 04:19:52 2018 +0900
@@ -17,8 +17,5 @@
 # Require `belongs_to` associations by default. Previous versions had false.
 Rails.application.config.active_record.belongs_to_required_by_default = true
 
-# Do not halt callback chains when a callback returns false. Previous versions had true.
-ActiveSupport.halt_callback_chains_on_return_false = false
-
 # Configure SSL options to enable HSTS with subdomains. Previous versions had false.
 Rails.application.config.ssl_options = { hsts: { subdomains: true } }