Two new values for the Clear-Site-Data header to help developers target clearing the prerender and prefetch cache: "prefetchCache" and "prerenderCache".
Currently, the only way to clear the prefetch and prerender cache is through either the Clear-Site-Data header "cache" value or manually having the UA clear their browsing data cache. With the increased adoption of Speculation Rules, developers want a way to target specifically clearing prefetches, prerenders, or both, without disrupting other session information, such as history, cookies, etc. By adding "prefetchCache" and "prerenderCache" values to the Clear-Site-Data response headers, there is an option to target only these specific caches.
Explainers: https://github.com/WICG/nav-speculation/blob/main/clear-site-data-integration.md