Test locally before you deploy: run our entire platform, right on your laptop! npm install netlify-cli -g and run ntl dev.
https://graphemica.com/%E2%98%B0
Алексей Родионов, [15 May 2020, 19:59:20 (15 May 2020, 19:59:55)]: ...Web Vitals (это LCP + FID + CLS):
LCP (Largest Contentful Paint):
https://web.dev/lcp/ https://web.dev/optimize-lcp/
FID (First Input Delay):
https://web.dev/fid/ https://web.dev/optimize-fid/
CLS (Cumulative Layout Shift):
https://web.dev/cls/ https://web.dev/optimize-cls/
TBT (Total Blocking Time):
TTI (Time to Interactive):
FCP (First Contentful Paint):
TTFB (Time to First Byte):
https://web.dev/time-to-first-byte/
А ещё есть вот такая библиотека:
https://github.com/GoogleChrome/web-vitals
И вот такое расширение для браузеров на основе Chromium: