Speed
Render-blocking scripts
Why it matters
Scripts in the head without async or defer stop the browser from showing the page until they download and run.
How to fix it
- Add defer (or async) to scripts that are not needed for the first render.
- Move non-critical scripts to the end of the body.
Check it with
- Page Speed Test – Lighthouse performance score, lab metrics and real-user Core Web Vitals for any page.
Scoring: a passed check earns its full weight, a warning half and an error none. How the SEO score works