Google has published Lighthouse extensions for Firefox. It is a web browsing tool that allows you to analyze page performance and web browsing. It is open source and has been running as an extension for Chrome since 2016. Lighthouse will now be available to 400,000 Firefox users.
Lighthouse reports page or application performance using data from the PageSpeed Insights API. The tool evaluates download speed, application problems, resource usage, the relevance of web technologies, etc. Lighthouse also advises on how to improve the performance, SEO parameters, and availability of the page or application.