MainWP Lighthouse Extension GPL Overview:
MainWP Lighthouse WordPress Extension is used for measuring the quality of your websites. It uses the Google PageSpeed Insights API to audit the performance, accessibility, and search engine optimization of your WordPress sites.
The MainWP Lighthouse Extension is used to automatically measure the quality of your Child Site(s). It audits the performance, accessibility, best practices, and search engine optimization of websites connected to your MainWP Dashboard.
This Lighthouse WordPress extension uses the Google PageSpeed Insights API which runs a barrage of tests against a Child Site and then generates a report on how well the Child Site did.
From here you can use the failing tests as indicators of what you can do to improve your website quality.