[web] stop adding an Expires header with all responses As per RFC 1945 (HTTP 1.0): If the date given is equal to or earlier than the value of the Date header, the recipient must not cache the enclosed entity. As per RFC 7234 (HTTP 1.1 Caching): If a response includes a Cache-Control field with the max-age directive (Section 5.2.2.8), a recipient MUST ignore the Expires field. Bottom line, the Expires header is now handled wherever the Cache-Control is handled: inside cache managers.