You don't want to revert to the older version, ie 56, because of security. You can download the ESR version which currently is at v52.5.0 and work with legacy add-ons. ESR will be at v52 until Firefox 60 when it will be 52.8.0. This will be the last version before upgrading to Quantum on ESR 59.1.0 which will be June 2018
Personally I've gone to ESR for the moment, that's the only way to keep Noscript working for now. Once NoScript has been released for the web extensions format of firefox 57 I'll go back to a release channel firefox within a week or so.
Esr is 52 based, a 59 based ESR doesn't exist yet and won't for months. ESR should work on any OS that a release version can work on, and ESR MIGHT support some OS's which can't run release but it's not certain to.