Merge pull request #39633 from gmcgibbon/document_javascript_path

Document config.javascript_path

guides/source/configuring.md

@@ -112,6 +112,8 @@ numbers. It also filters out sensitive values of database columns when call `#in
 
 * `config.force_ssl` forces all requests to be served over HTTPS, and sets "https://" as the default protocol when generating URLs. Enforcement of HTTPS is handled by the `ActionDispatch::SSL` middleware, which can be configured via `config.ssl_options` - see its [documentation](https://api.rubyonrails.org/classes/ActionDispatch/SSL.html) for details.
 
+* `config.javascript_path` sets the path where your app's JavaScript lives relative to the `app` directory. The default is `javascript`, used by [webpacker](https://github.com/rails/webpacker). An app's configured `javascript_path` will be excluded from `autoload_paths`.
+
 * `config.log_formatter` defines the formatter of the Rails logger. This option defaults to an instance of `ActiveSupport::Logger::SimpleFormatter` for all modes. If you are setting a value for `config.logger` you must manually pass the value of your formatter to your logger before it is wrapped in an `ActiveSupport::TaggedLogging` instance, Rails will not do it for you.
 
 * `config.log_level` defines the verbosity of the Rails logger. This option