Preload (spec) is a new web standard aimed at improving performance and providing more granular loading control to web developers. It gives developers the ability to define custom loading logic without suffering the performance penalty that script-based resource loaders incur.
A few weeks ago, I shipped preload support in Chrome Canary, and barring unexpected bugs it will hit Chrome stable in mid-April. But what is that preload thing? What does it do? And how can it help you?
<link rel="preload"> is a declarative fetch directive.
In human terms, it’s a way to tell a browser to start fetching a certain resource, because we as authors (or as server administrators, or as smart-server developers) know that the browser is going to need that particular resource pretty soon.
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