Cross Domain - CORS is a Chrome extension developed by Mai Tan. It is a free tool designed to help web developers and related domains deal with cross-domain issues, specifically Cross-Origin Resource Sharing (CORS) problems.

This extension offers several useful features, including the ability to allow cross-domain requests, customize URL patterns based on JavaScript Regex, and enable or disable the extension as needed. The interface is user-friendly and easy to navigate, making it accessible for developers of all skill levels.

Under the hood, Cross Domain - CORS modifies the header response from the server and adds additional headers to allow CORS requests. These headers include Access-control-allow-origin, Access-control-allow-methods, Access-control-allow-headers, and Access-control-expose-headers. It's important to note that this extension is intended for development purposes only.