Is it possible to use my personal MacBook Pro as a secondary monitor to my company MacBook Air via SideCar or some other option?…
I’m on the road so away from my doc at home w/ external monitor but it sure would be nice to have a secondary monitor while I work on the road…
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Rhett
It will be with macOS Monterey this fall. That's one of the new features -- to use another Mac as an AirPlay receiver so it can be a second screen. Sidecar is for a Mac to an iPad, not a Mac to a Mac.
You should be able to do AirPlay to another Mac right now with https://www.airserver.com/Mac but it has been a long time since I tried that.
But keep in mind that something like this is a lot slower than a real display that has a direct connection (DisplayPort/DVI/HDMI) to your Mac's graphics output. For a text-based app (Pages, Mail, Reminders, Calendar, etc) or a static web page it should be fine. For graphics work, video work, games, etc, you should just get a real second screen.