I would like to use a mid-2011 iMac as an external monitor
I would like to use a mid-2011 iMac as an external monitor for a 2019 iMac. The 2011 has a mini display port (with lightening bolt). The 2019 has a Thunderbolt (looks like a USB-C). I ordered a cable with one end a USB-C and the other a mini-display port but this evidently doesn't work. But I cannot seem to find a true cable that is Thunderbolt -> Mini Display Port.
Any suggestions?
Thank you.