iMac won't see iPhone
I am running 10.12.6 on a 2017 iMac. When connecting my iPhone 11 on IOS 14.4.2, the iMac damands a software update in order to see the phone. I do not want to update from Sierra to the current MacOS. What is updated if I click install?
iMac 21.5″ 4K, macOS 10.12