Perhaps your browser is being directed to a page not owned by google. I don't get an SSL warning in Chrome or Firefox (Windows 10). From the site: "With action

Perhaps your browser is being directed to a page not owned by google. I don't get an SSL warning in Chrome or Firefox (Windows 10). From the site: "With actionable guidance and analysis, web.dev helps developers like you learn and apply the web's modern capabilities to your own sites and apps." It includes a web version of the Lighthouse website measurement tool. It also has guides for various web dev topics. The topics can be browsed normally, but I think most users will discover topics by the measurement tool showing the user guides to improve their website.