There are a few ways to uncheck make this my main display in Windows 10. One way is to use the Display settings.
- For that, you have to go to Settings > System > Display.
- Here you will see the option “This is my main display.”
- You can uncheck this box to make another display the main display.
Another way to uncheck make this my main display is to use the DisplayFusion Settings.
You can use this setting to uncheck “Make This My Main Display” in the context menu for all monitors, but you cannot use this setting to make a specific monitor the main display.