diff --git a/config.ru b/config.ru
index ad1fbf29..949a0571 100644
--- a/config.ru
+++ b/config.ru
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 # This file is used by Rack-based servers to start the application.
 
 require_relative 'config/environment'
 
 run Rails.application
-Rails.application.load_server
+Rails.application.load_server if Rails::VERSION::MAJOR == 6
diff --git a/config/initializers/cookies_serializer.rb b/config/initializers/cookies_serializer.rb
index 5a6a32d3..f51a497e 100644
--- a/config/initializers/cookies_serializer.rb
+++ b/config/initializers/cookies_serializer.rb
@@ -2,4 +2,4 @@
 
 # Specify a serializer for the signed and encrypted cookie jars.
 # Valid options are :json, :marshal, and :hybrid.
-Rails.application.config.action_dispatch.cookies_serializer = :json
+Rails.application.config.action_dispatch.cookies_serializer = :hybrid