Dev Headers is a free Chrome add-on developed by craig.francis that aims to enhance the web development experience. This tool adds a header for dev websites, making it easier to read Content-Security-Policy (CSP) and Permissions-Policy (PP) headers. It also checks that all other related headers have been properly set for the HTML and linked resources, such as Referrer-Policy.

One of the key features of Dev Headers is the ability to set a "X-Dev-Key" header on all requests to your server. This header value is typically kept as a secret and allows your server to enable additional debug information. It is recommended that your server also checks the source IP address and ensures that you are logged in for added security.

Dev Headers is a valuable tool for web developers who want to streamline the process of reading headers and ensuring proper configuration. With its user-friendly interface and helpful features, this add-on is a must-have for developers working on web projects.