We are running a mid 2013 Air on Big Sur 11.6.8 and an iMac mid 2020 on Monterey 12.6
We've suddenly noticed that each machine can 'see' and open a copy of the screen of the other while working - in Safari - Firefox etc.
I've tried system preferences - screen sharing, display etc options and nothing stop this sharing of screens. Perhaps we have been hacked?
Please help us turn this off.
iMac 27″, macOS 12.6
Hi jonathanfromlittlegrove,
Thanks for coming to Apple Support Communities for help today.
Hacking seems highly unlikely. Go ahead and double-check all the steps here: Share the screen of another Mac and make sure all settings are off.
If that still doesn't explain it, let us know further details.
Are you using the same Apple ID on both computers?
Does this only happen with the browsers? Or will it happen with other apps?
Try starting both Mac computers in safe mode. Does it still happen? Here is How to use safe mode on your Mac.
Let us know more details.
Have a fantastic day!
Stop mirroring between MacBook Air and iMac
