Is Notchy's Face Unlock secure?
It's a convenience feature, not a security feature. A webcam can't measure depth like Face ID's infrared sensor, so a good enough photo or video of you might unlock your Mac. Use it where that trade-off is fine, and keep your password and Touch ID for anything sensitive.
Good to know
Your face data and password are stored only in your macOS Keychain, never on disk or online, and recognition runs on your Mac.
Every unlock requires a head turn and a blink, matching is done against several reference scans, and macOS still requires your password after every restart.
See also
Updated
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