Explanation
If a developer leaves debug mode turned on in an environment, the user will begin getting JavaScript limit exceptions. Debug mode is a setting that enables more detailed logging and error reporting for Lightning web components. However, it also increases the size and complexity of the JavaScript code that is delivered to the browser, which can cause performance issues and JavaScript limit exceptions. The JavaScript limit exceptions are errors that occur when the browser reaches its maximum capacity for executing JavaScript code, such as memory heap size or script execution time. The performance of the org will not become slower each day, as debug mode only affects the client-side performance, not the server-side performance. The org will not turn off debug mode after 72 hours, as debug mode is a persistent setting that can only be changed manually by an administrator. A banner will not be displayed to the user indicating that the org is in debug mode, as debug mode is a transparent setting that does not affect the user interface. Salesforce References: Lightning Web Components Developer Guide: Debug Your Code, Lightning Web Components Developer Guide: JavaScript Limit Exceptions

The Global JavaScript Object that should be extended when writing custom Remote Actions is CCRZ.cc. This object contains all the Remote Actions that are defined in the cloudcraze managed package, which can be overridden or extended by subscriber code. The object also provides a mechanism for registering custom Remote Actions that can be invoked by the user interface components. For example, CCRZ.cc.customAction = function(params, callback){ // do something } will define a custom Remote Action named customAction that can be called by CCRZ.cc.customAction(params, callback). Salesforce Reference: B2B Commerce and D2C Commerce Developer Guide, Remote Actions

Explanation
To enable the ability to add new shipping and billing addresses during checkout, a developer should enable Buyer Managed Contact Point Addresses within the Shipping Address standard component in the Checkout subflow. The Buyer Managed Contact Point Addresses is a feature that allows customers to add, edit, or delete their shipping and billing addresses during checkout. The developer can enable this feature bysetting the buyerManagedContactPointAddressesEnabled attribute to true in the Shipping Address standard component in the Checkout subflow. The Shipping Address standard component is a component that displays and collects the shipping address information for the cart or order. The Checkout subflow is a subflow that defines the steps and components for the checkout process in the storefront. Creating a new shipping address checkout subflow that utilizes the Buyer Managed Contact Point Addresses component is not a valid way to enable this feature, as there is no such component as Buyer Managed Contact Point Addresses. Enabling Buyer Managed Contact Point Addresses within Commerce Administration is not a valid way either, as this feature is not configurable in Commerce Administration. Creating a Lightning web component that enables this functionality and replaces the current shipping address screen within the Checkout subflow is not a valid way either, as this is unnecessary and complicated when there is already a standard component that supports this feature. Salesforce References: [B2B Commerce Developer Guide: Buyer Managed Contact Point Addresses],
[B2B Commerce Developer Guide: Shipping Address Component], [B2B Commerce Developer Guide:
Checkout Subflow]