Can I still boot to Sierra after High Sierra firmware update?
I'm currently running Sierra, but want to install and run High Sierra on another internal hard drive to see if all my apps are compatible before committing permanently. When I was doing the installation of High Sierra, I got the notice for the firmware update. My question is, if I do the firmware update, will it affect being able to go back and boot into Sierra without any problems? I also have an old copy of Snow Leopard on another drive as well, that I need for running Nikon Scan. Will this firmware update cause me problems with all this?
If anyone answers this, I thank you in advance...