Max-age=0 signifies that the reaction is straight away stale, and must-revalidate signifies that it should not be reused without the need of revalidation as soon as it can be stale — so, in combination, the semantics appear to be the same as no-cache. It states "there is no cause" to https://jeffreyzwsng.blogpixi.com/36607099/the-smart-trick-of-coldfire-carts-that-nobody-is-discussing