Make IE cache the resources but always revalidate

I’ve eventually figured it out. Here is an explanation and a tested solution. The following site confirms my observation: http://blog.httpwatch.com/2008/10/15/two-important-differences-between-firefox-and-ie-caching/ It says that IE does not locally store pages with the ‘no-cache’ directive and hence always sends an unconditional request. There’s also a MS support article – https://support.microsoft.com/help/234067/ – which confirms this: “Internet Explorer supports … Read more

How long is a 302 redirect saved in browser?

It shouldn’t be cached at all unless there’s also a Cache-Control or Expires header returned by the web server. According to RFC 2616, section 10.3.3 302 Found The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. … Read more

Expires vs max-age, which one takes priority if both are declared in a HTTP response?

See this answer: Difference between three .htaccess expire rules If a response includes both an Expires header and a max-age directive, the max-age directive overrides the Expires header, even if the Expires header is more restrictive. This rule allows an origin server to provide, for a given response, a longer expiration time to an HTTP/1.1 … Read more

Chrome browser is not sending if-modified-since header to server

After spending half a day on this yesterday, I tracked down what was causing the issue for me. So long as you have the Chrome object inspector/Client Debugger/Network monitor/Thing that pops up when you hit F12, Chrome will not send cache request headers. Period. (update: in newer versions of Chrome, there is a checkbox “Disable … Read more