MacOS tells me that my phone is offering a network connection when I connect cable
Hi, I back up both my iPad Air 2 and my iPhone Xr to my Mac Pro 5,1 Mojave using a cable (old school, none of this iCloud business). Every time I connect one of these devices to the computer, the Mac tells me that there is a new network interface present, and would I like to open System Preferences to manage it? So I dutifully click through to System Preferences, and see the list of usual network interfaces: Ethernet 0, Ethernet 1, wifi, bluetooth. I click on the '+' button to add what I presume will be some USB network connection, but no joy there: I see VPN and 6to4 and another one that I can't recall, but nothing that looks phone-related. Any idea why this pops up, and how can I get rid of the annoying pop-up-to-nowhere?