The Speculation rules is a powerful API. It quickly reached broad adoption, even though it’s Chromium-only for now.
Cloudflare estimates it can save ~30.000 years of loading time per year, making it potentially more impactful than the Core Web Vitals initiative, which saved 10.000 years of waiting time in 2023.
Your website may have it, as WordPress, Cloudflare, and Shopify have it enabled by default. Improve the prefetching rates by applying some changes.
Remove redirects
As many configurations use conservative eagerness rules, removing redirects is going to improve the prefetching rates, as the late activation(conservative eargness) can still work.
Use this bookmarklet that checks for internal redirect links.
Upgrade the eagerness
Although conservative eagerness offers no waste, as activation is on pointerdown/finger on the screen, its prefetching rates may be low(in the 40s%), as it happens late.
Upgrade the eagerness so activation can happen earlier.
Update dynamic links to anchor links
Platforms such as Replo may use dynamic links for internal linking. Change them to anchor links(<a>) so Speculation rules can work.
Use expects_no_vary_search & no-vary-search header
Use the speculation rules expects_no_vary_search setting to match the no-vary-search headers, and prevent redundant network requests for the same requests but with different queries.
Remove cookies
Google Search prefetches the search results, but only if the site doesn’t have cookies, as privacy protection and accurate page loads are prioritized.
Cache your HTML on Cloudflare
Cloudflare enables conservative prefetch for all sites, but if your site isn’t caching the HTML on the edge, then it’s going to cannibalize your platform prefetch settings(if there are any), and both aren’t going to work, as Cloudflare only prefetches cacheable requests.
Only 15% of Cloudflare APO(Cloudflare’s WordPress product which main feature is full HTML cache) sites have full HTML cache enabled.
