The on-prefetch-activation HTTP response header enables servers to specify a telemetry endpoint that the browser notifies when a prefetched resource is used for navigation. Developers gain a reliable signal to measure the precision and performance impact of their prefetch strategies.
The API is proposed for a reliable measurement of whether a prefetch page is activated. This allows precise visit statistics for the prefetched page without cache interference.
Explainers: https://github.com/explainers-by-googlers/prefetch-activation-beacon