Temporary Solution to the Pixel 4 Face Unlock Closed Eyes Vulnerability

The Pixel 4 has launched with a vulnerability that allows unlocking the phone with one's face, even when the eyes are closed. Google promised to address that in a future update, but until then, there's an easy temporary solution. Just use the Lockdown feature.

Lockdown is a security feature that was introduced in 2018 with Android 9 (Pie). Lockdown allows your phone to temporarily stop accepting biometric authentication, like fingerprints and face-prints, and enforce using your password or pattern to unlock; it also hides all notifications on the lock screen.

To enable Lockdown on Android 10, go to Settings -> Display -> Lock screen display and switch on the  Enable lockdown option. After that, you can simply press and hold the power button and then select the Lockdown option.