Comparison
Cache-ControlvsConditional request
Cache-Control
you deployed a fix and the browser served the old file anyway, from its own disk cache.
The header that tells the browser and any intermediate cache how long a response may be reused and under what conditions. The directives are routinely misread: `no-cache` means revalidate before use rather than do not store, and only `no-store` actually prevents caching. Getting this wrong on an HTML entry point pins users to an old build for as long as the max-age lasts.
Full entry →Conditional request
the browser asked whether its copy was still current and got back a 304 with no body at all.
A request carrying a validator from a previously cached response, so the server can answer 304 Not Modified instead of resending the body. It saves the payload but not the round trip, which is why a page full of revalidations still feels slow on a high-latency connection. Assets with a content hash in the name should never reach this path, because they should be cached as immutable instead.
Full entry →