It's true, Firefox doesn't cache everything. The rules (?) are set out in this article: https://developer.mozilla.org/en-US/d.../Using_Firefox_1.5_caching.

To overwrite the cache-related headers before Firefox sees them probably requires some kind of external proxy, or maybe an extension could do it. I didn't see any extension purpose built for this, but did see a discussion of one on a website: networking - Force Firefox to cache a URL for a specific period of time - Super User.

Thanks for that useful information.

I installed a version of that script (just removed the if url check so it applies to every site). It works for some sites, not others (like this one).

There definitely needs to be a setting added to firefox to override the pageshow/pagehide event hijacking user control over caching. I shudder to think how many billions of unnecessary packets are sent every day and how much time and bandwidth is wasted reloading information that is exactly the same and already sitting on your computer [Idiocracy].