Two preconnect lines shaved 300ms off LCP
When your page pulls a font or script from another website, the browser must first 'introduce itself' to that server: look up the address, shake hands, agree on security. That handshake takes time. Think of it like queuing to get into a building before you can even ask for what you need.
A site loaded fonts from Google's servers, but the browser only started the handshake when it hit the font line, deep in the page.
The fix told the browser to start early:
— Added <link rel="preconnect"> for the two font domains in the <head>.
— The handshake happened in parallel with everything else.
Result: the font arrived ~300ms sooner, and since text was the LCP element, LCP improved too.
Try this: list your third-party domains. Preconnect to the two or three you rely on most.
Vitals 101
@CoreVitals101
Two preconnect lines shaved 300ms off LCP
Этот пост опубликован в Telegram-канале Vitals 101. Подписаться можно по ссылке: @CoreVitals101.