I guess it's this product: https://www.ccsmax.com/firefox/ Please tell them you want a version compatible with Firefox 57. If they can do it for Chrome, most likely they can do it for Firefox. But if this product is essential to your productivity ''right now,'' and you do not want to use Chrome for it, you may have to use an earlier version of Firefox. Please: * Make a backup: [[Back up and restore information in Firefox profiles]] * Then see: [[Install an older version of Firefox]] If they tell you it's going to be a long time to get a compatible extension, consider whether you might want to switch to the Extended Support Release of Firefox 52. That's Firefox 52 plus additional plugin compatibility plus security fixes. It will be supported through next Spring. More info on ESR: https://www.mozilla.org/firefox/organizations/faq/ Originally developed for businesses that prize stability over features, lots of individual users now use Firefox 52 ESR because they need backwards compatibility. Note that some of your add-ons might have "moved on" beyond Firefox 52 and need to be rolled back as well, but it's hard to advise without knowing specifics.