Enable almost all Rails 7.1 framework defaults

config/application.rb

@@ -29,6 +29,7 @@ class Application < Rails::Application
 
     # Initialize configuration defaults for originally generated Rails version.
     config.load_defaults 7.0
+    config.active_support.cache_format_version = 7.1
 
     # Please, add to the `ignore` list any other `lib` subdirectories that do
     # not contain `.rb` files, or that should not be reloaded or eager loaded.

config/initializers/new_framework_defaults_7_1.rb

@@ -23,13 +23,14 @@
 # Remove the default X-Download-Options headers since it is used only by Internet Explorer.
 # If you need to support Internet Explorer, add back `"X-Download-Options" => "noopen"`.
 #++
-Rails.application.config.action_dispatch.default_headers = {
-  'X-Frame-Options'                   => 'SAMEORIGIN',
-  'X-XSS-Protection'                  => '0',
-  'X-Content-Type-Options'            => 'nosniff',
-  'X-Permitted-Cross-Domain-Policies' => 'none',
-  'Referrer-Policy'                   => 'strict-origin-when-cross-origin'
-}
+# TODO: enable this one by itself, after the rest
+# Rails.application.config.action_dispatch.default_headers = {
+#   'X-Frame-Options'                   => 'SAMEORIGIN',
+#   'X-XSS-Protection'                  => '0',
+#   'X-Content-Type-Options'            => 'nosniff',
+#   'X-Permitted-Cross-Domain-Policies' => 'none',
+#   'Referrer-Policy'                   => 'strict-origin-when-cross-origin'
+# }
 
 ###
 # Do not treat an `ActionController::Parameters` instance
@@ -138,7 +139,7 @@
 # servers, first deploy without changing the serializer, then set the serializer
 # in a subsequent deploy.
 #++
-Rails.application.config.active_support.message_serializer = :json_allow_marshal
+Rails.application.config.active_support.message_serializer = ActiveSupport::JSON
 
 ###
 # Enable a performance optimization that serializes message data and metadata
@@ -173,7 +174,8 @@
 # The previous behavior was to validate the presence of the parent record, which performed an extra query
 # to get the parent every time the child record was updated, even when parent has not changed.
 #++
-Rails.application.config.active_record.belongs_to_required_validates_foreign_key = false
+# TODO: enable this one by itself, after the rest
+# Rails.application.config.active_record.belongs_to_required_validates_foreign_key = false
 
 ###
 # Enable precompilation of `config.filter_parameters`. Precompilation can