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Choose Apple > System Preferences (Mac OS 11 and 12), or Apple > System Settings (macOS 13 and 14).
- macOS 11/12
Click Desktop & Screen Saver.
Click the Screen Saver tab.
Select a screen saver.
Under Start after, set to 30 minutes or longer.
Close the Desktop & Screen Saver window.
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- macOS 13/14
- Go to Apple > System Settings > Screen Saver.
- Select a screen saver.
- Go to Apple > System Settings > Lock Screen.
- Change the drop-down in Start Screen Saver when inactive to 30 minutes or longer.