They might cache it if the server allows them to cache it. But evil servers don't. Example: gravatar.com gives an expiration time of 5 minutes. curl -q -i --

They might cache it if the server allows them to cache it. But evil servers don't. Example: gravatar.com gives an expiration time of 5 minutes. curl -q -i --output - https://www.gravatar.com/avatar/70d9b050bfe39350c234d710fadfcd39 https://www.gravatar.com/avatar/70d9b050bfe39350c234d710fadf... | grep -a xpires expires: Fri, 12 Feb 2021 11:54:40 GMT