I few years ago my workarounds to adding separate stop and refresh buttons stopped working. A solution was given <a href="https://support.mozilla.org/en-US/questions/1000785">here</a>. In the most recent Firefox updates, this solution also no longer works and the other solutions I have found are ones that would change functionality more then I would like. This is more important today as some websites seem to go through several cycles of auto-refreshing certain elements. I don't want to go to stop a website from loading and end up refreshing even more of it then already was being refreshed. I'm running Firefox 56.0.1 64 bit on Windows 10 on an old Dell laptop. Comming up with a permanent stop (that keeps a website from loading any more content to my machine that it has already) is also something I'm interested in but one problem at a time (I should also look into this some more to see if there is already a solution).