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jvjvalerio

macrumors newbie
Original poster
Feb 24, 2025
1
0
After upgrading to macOS Sequoia 15.3.1, our iMac M3s connected to projectors no longer mirror their displays by default; instead, they extend the desktop. This has caused confusion for users who expect the displays to be mirrored when logging into the iMacs at their podiums for presentations.

How can I configure the system to default to display mirroring, regardless of the user logging in?

I attempted the following command but did not achieve the desired result:
"sudo defaults write /Library/Preferences/com.apple.windowserver DisplayMirroring -bool true"

I've also tried pushing a persistent mobileconfig file that does not maintain the display mirroring after rebooting the device.
 
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