Prerender Test

Test <link rel="prerender">.

Prerender

• zmmbreeze/blog#21

• https://developer.mozilla.org/en-US/docs/Web/API/Document/visibilityState

<a ping="ping.gif">

• https://developer.mozilla.org/zh-CN/docs/Web/HTML/Element/a

navigator.sendBeacon

• https://developer.mozilla.org/en-US/docs/Web/API/Navigator/sendBeacon