 Sites can use the Speculation Rules API to programmatically tell Chrome which pages to pre-render, creating a better user experience by reducing page navigation time. Now the API includes support for document rules. This is an extension to the Speculation Rules syntax that lets the browser obtain the list of URLs for speculative loading from elements in a page. Document rules may include criteria for which of these links can be used. This, coupled with a new ignorance field, allows you to automatically pre-fetch or pre-render links on pages immediately, on hover, or on mouse down. A separate change allows specifying speculation rules using the Speculation Rules HTTP response header. The header is an alternative to using inline script elements.