Ocker3 wrote:Ctrl-F5 for force refresh, which I assume is still valid. Historically, F5 only checked the local host for updates, Ctrl-F5 goes back to the original host.
A regular refresh (F5 or Ctrl+R) causes the browser to make an HTTP request with the "If-Modified-Since" header. The date is set to the date the cached object was retrieved. If the resource hasn't been modified since then, the server responds with an HTTP 304 "Not Modified" status, and an empty body. If the resource *has* changed, the server responds with a regular HTTP 200 "OK" status, and sends the content in the body. In other words, the browser asks the server, "Send me again if it's changed since the last time I looked". The server either says "It hasn't changed" or "Here's the new content".
A forced reload (with Ctrl+Shift+R or Ctrl+F5) causes the browser to make an unconditional HTTP request, and *always* transfers a new copy of the resource. Any caching is discarded. It's mainly useful for cases where you believe the server is not tracking/reporting modification dates correctly.
Don't overuse forced reload; it significantly increases load on the server for no good reason.