Choose Apple > System Preferences (macOS 11 or 12)or Apple > System Settings (macOS 13 and up).
- macOS 11/12
Click Users & Groups.
Click the account whose settings you want to change.
Click Login Options.
Clear the Show fast user switching menu as <Full Name> check box.
Click the lock to prevent additional changes to the settings.
Close the Users & Groups window.
- macOS 13 /14and up
Open Terminal.
Type the following command:
sudo defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool false, then press the Enter key.- Enter your system password.
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