If you'd like to try out Firefox Quantum on Windows without impacting your existing local or portable version, you can grab either the 57 Beta or the 57 Develop

If you'd like to try out Firefox Quantum on Windows without impacting your existing local or portable version, you can grab either the 57 Beta or the 57 Developer version in portable form from PortableApps.com. It's self-contained with its own profile and settings that are kept separate from the normal install. It doesn't require admin rights to extract it and try it out. And you can "uninstall" it just by deleting a folder. https://portableapps.com/news/2017-09-28--try-firefox-quantum-57-risk-free https://portableapps.com/news/2017-09-28--try-firefox-quantu...