Testcase for cache with Vary Cookie

test cookie that has been sent to the server
The page generation timestamp (on the server)
The page loading timestamp (in the browser)
Elapsed seconds after the page generation
The script in the browser was not performed.

Additional tools for manual testing

Note: if the elapsed time doesn't grow on the page reloads with the same cookie it means that your browser doesn't use the cache at all. For example, like Internet Explorer.

Back link: the bug 71509 in Safari.