Google Mail Checker is an open-source extension designed for Firefox that enables users to easily monitor their Gmail accounts. This tool provides real-time notifications for new emails, helping users stay updated without needing to manually refresh their inbox. The extension requires only one permission to search for open Gmail tabs, ensuring a seamless experience while safeguarding user privacy.

As a social networking tool, Google Mail Checker enhances communication efficiency by allowing quick access to Gmail notifications directly within the Firefox browser. It serves as a valuable addition for users who prefer an integrated approach to managing their emails while browsing. The source code is available for those interested in exploring its functionality further.