Second Monitor connection
I have a new iMac (27-inch, Retina 5k display 2020, Big Sur 11.2) to which I'm trying to connect an old iMac (27-inch, late 2013, El Capitan 10.11.6) as a second monitor. I'm using a USB-C adapter and Thunderbolt 2 cable to connect the two iMacs. I've followed every online tutorial to troubleshoot this, including testing the adapter and cable. Why is it not working? Could the USB-C port on the new iMac be bad?
iMac 27″, OS X 10.11