Browser & Web Performance · Middle · Question 37 of 75

What does the Speculation Rules API allow?

<script type="speculationrules">
{ "prerender": [{ "where": { "href_matches": "/product/*" }, "eagerness": "moderate" }] }
</script>

1Running JavaScript speculatively on a worker
2Predicting the user's next click with machine learning on the server
✓Correct answer: Declaratively prefetching or prerendering likely next pages so navigations become near-instant

Explanation

Prerendering loads and renders the page in the background. eagerness controls when, e.g. on hover for moderate.

Further reading

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