Break long JavaScript tasks over 50 ms into chunks with scheduler.yield(), free the main thread between the chunks and keep the INP steadily under 200 ms.
The Long Animation Frames API reveals since Chrome 123 exactly which script causes a slow INP interaction -- so you optimize deliberately instead of blindly.
Every redirect costs a round trip before the first byte. Learn how to detect HTTP, www and slug chains and reduce them to a single hop without losing SEO value.
How a service worker with precaching keeps critical files local, serves repeat visits with almost no server round trip and when the effort truly pays off.
Stop optimizing Largest Contentful Paint blindly: measure TTFB, load delay, load time and render delay individually and target the biggest lever deliberately.
Status code 103 per RFC 8297: how the server sends preconnect and preload hints during think time, how the nginx rollout looks and where the honest limits run.
Cookie banners move LCP, INP and CLS: how to measure the consent layer impact in the field, rebuild it properly and take it out of the critical path for good.
content-visibility and CSS containment limit the rendering work of long pages to the visible area - with placeholder heights that avoid new layout shifts.
Compression dictionary transport per RFC 9842: how browsers and servers ship bundles as deltas against the previous version - patterns, configuration, fallback.