If you want to run legacy extensions, install FF ESR.
Most of them won’t run on 57.
k thanks- I’ll stick with firefox 54 for now- if i can find out how to turn off updates- in hte update panel it just says soemthign about search engine updates- not the browser update
Where does one find Firefox ESR, and how long is it expected to be supported with security fixes? If it's for at least a few more months, it would be worth installing it while I continue to try out other browser. I'm leaning toward Opera. I want to like Brave but I'm not enamored with its lack of flexibility in script control (it is not as useful as uBlock Origin or even NoScript).