Google Mail Checker автор michael-mml

An open-source, Firefox port of Google Mail Checker on Chrome/Chromium: https://chrome.google.com/webstore/detail/google-mail-checker/mihcahmgecmbnbcchbopgniflfhgnkff?hl=en.

Requires 1 permission (to search for open Gmail tabs).

See here for source code: https://gitlab.com/michael-mml/ff-google-mail-checker