I’d like to know if it’s possible to know what macOS version is installed in a Mac (such as macOS 10.14.3) if you can get the firmware version (such as in System information).
I sometimes cannot log into a customer’s Mac because it’s Filevault encrypted. So this way, by starting the Mac from a macOS external volume, I can get the firmware version, and, hopefully, the macOS version.
Is there any website that lists firmware version and corresponding macOS version? such as:
Boot ROM Version: 238.0.0.0.0 macOS 10.14.4
or the same firmware version could be in different versions of macOS?
Any help much appreciated.