master.key is now used in production environment

config/environments/production.rb

@@ -17,7 +17,7 @@ Rails.application.configure do
 
   # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
   # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
-  # config.require_master_key = true
+  config.require_master_key = true
 
   # Disable serving static files from the `/public` folder by default since
   # Apache or NGINX already handles this.