Web.dev is the ultimate resource for developers of all backgrounds to learn, create, and solve on the web. It's meant to not only educate developers, but help them apply what they've learned to any site they work on, be it personal or business.
The PSI UI redesign aims to improve the presentation of the report data and add clarity and granularity to the data available in the report. The new UI is aimed to be more intuitive and helps developers quickly discover lab and field performance insights for their pages.