Also, in Chrome, if and only if you have the dev tools open, right clicking the reload button will give you a menu with the options "Normal Reload", "Hard Reload", and "Empty Cache and Hard Reload". The third option will ensure that requests initiated by JS or that otherwise weren't part of the page load also won't be served from cache.
I'm pretty sure I remember using it earlier than that but can't be 100%.
[1] https://bugzilla.mozilla.org/show_bug.cgi?id=46845#c7
[2] http://www.bu.edu/uis_web3270/en/doc/troubleshoot/pd_ck_down...
But it hasn't always been easy to find documentation about it, thanks to a combination I think of "simplifying" everything and Google not delivering correct results since somewhere around 2010.
Thankfully now there is Kagi that actually makes a bug report if you provide them with an example that doesn't work.
Sorry for the misinformation