Try : https://addons.mozilla.org/en-US/firefox/addon/feedbroreader/ People from Sage have moved to that. Comments in Sage forum are positive and as well people wanting to donate money to Sage to make it compatible with 57+. https://www.howtogeek.com/333230/why-firefox-had-to-kill-your-favorite-extension/ https://www.howtogeek.com/334111/firefox-quantum-isnt-just-copying-chrome/ https://www.howtogeek.com/332449/whats-new-in-firefox-quantum/ https://addons.mozilla.org/en-US/firefox/extensions/ https://mozilla.github.io/extension-finder/ If not updated to 57.0.2 Please do so. https://support.mozilla.org/en-US/kb/update-firefox-latest-version Please update Flash 27.0 r0 Flash Player Version: 28.0.0.126 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only> Going back : unfortunately 56.0.2 and below is no longer safe to use for every day use do to secuity issues, but 52.5.2 ESR is. It will continue to get security updates until May 2018, and you can download and install it from this page: https://www.mozilla.org/en-US/firefox/organizations/all/ <b>Note : Legacy Extensions will be deleted or removed in any version update after May 2018</b>. You should make a backup of your Profile before going back and just because: https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer Please let us know if this solved your issue or if need further assistance.

Thanks for the explanation. I tried feedbroreader but can't get that to work in FF. In fact there's more of the extensions that I used that don't work with/in the new version of FF than do. I think that it's goodbye because I can't see any improvement in the new version of FF and it must be downhill from hereon. John