← Chrome 147 reference

v147 · html · covered on mdn

JSON and style support for link rel=modulepreload

<link rel="modulepreload"> can now preload JSON modules (as="json") and CSS modules (as="style") in addition to JavaScript modules. This allows pages to declaratively preload all their module graph dependencies — including non-JS modules — so they are parsed and stored in the module map before they are needed.

this feature is documented on MDN

MDN: rel="modulepreload"

MDN's modulepreload reference covers all supported as values including "json" and "style", with usage examples and browser compatibility. gendn doesn't duplicate that here.

quick reference

New as valuesas="json" — preload a JSON module; as="style" — preload a CSS module
Usage<link rel="modulepreload" as="json" href="/data/config.json">
EffectJSON/CSS module is fetched, parsed, and inserted into the module map so import … assert {type: 'json'} or import … assert {type: 'css'} hits the cache
Shipped inChrome 147 (desktop + Android)
ChromeStatus5202661416763392 — JSON and style support for link rel=modulepreload
SpecHTML Living Standard — modulepreload
Source: MDN, chromestatus, May 2026.