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herrkessler/check-webp.js

Forked from jakearchibald/1.js
Last active August 17, 2017 07:45
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check-webp.js
async function supportsWebp() {
if (!self.createImageBitmap) return false;
const webpData = 'data:image/webp;base64,UklGRh4AAABXRUJQVlA4TBEAAAAvAAAAAAfQ//73v/+BiOh/AAA=';
const blob = await fetch(webpData).then(r => r.blob());
return createImageBitmap(blob).then(() => true, () => false);
}
addEventListener('install', event => {
event.waitUntil(async function() {
if (await supportsWebp()) {
document.body.classList.add('webp');
}
else {
document.body.classList.add('no-web');
}
}());
});
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