Enables prefetch to match even if URL query parameters change. The No-Vary-Search HTTP response header declares that some or all parts of a URL's query can be ignored for cache matching purposes. It can declare that the order of query parameter keys should not cause cache misses, that specific query parameters should not cause cache misses or that only certain known query parameters should cause cache misses. It could apply to multiple caches, but this entry refers to support for prefetch cache.
One of the most important cache keys for web resources is the resource's URL. However, sometimes multiple URLs can represent the same resource. This leads to caches not always being as helpful as they could be: if the browser has the resource cached under one URL, but the resource is then requested under another, the cached version will be ignored. Via a new HTTP header, No-Vary-Search, resources can declare that some or all parts of the query can be ignored for cache matching purposes.
Explainers: https://github.com/WICG/nav-speculation/blob/main/no-vary-search.md