速度
阻塞渲染的脚本
为何重要
Scripts in the head without async or defer stop the browser from showing the page until they download and run.
如何修复
- Add defer (or async) to scripts that are not needed for the first render.
- Move non-critical scripts to the end of the body.
使用以下工具检查
- Page Speed Test – Lighthouse performance score, lab metrics and real-user Core Web Vitals for any page.
评分：通过的检查获得全部权重，警告获得一半，错误则不得分。 SEO 评分如何运作