https://wccftech.com/today-in-android-oneplus-3-3t-get-face-unlock-zte-axon-7s-oreo-update-leaked-and-more/

After the launch of a new device, several manufacturers often met out step-motherly treatment to their predecessors. Thankfully, OnePlus isn’t one of them and continues to update the nearly two-year-old OnePlus 3/3T regularly. As a cherry on top, they even port features from newer devices on to older, compatible ones. In the latest update, the OnePlus 3 and 3T get their successor’s Face Unlock feature, along with a few other perks including the latest May security patch for Android. Here’s the complete changelog:

The update is rolling out OTA and should hit your device within the week.