Unlocking phone without pressing power button, using only fingerprint sensor

A feature which is common on most other phones with fingerprint sensors is the ability to unlock the phone while the screen is black. Simply placing a finger on the sensor will unlock the device. I recently bought a razer phone 2 because of the intelligent placement of the sensor, thinking I could lift my phone out of my pocket and already have it unlocked. Sadly after lots of looking there is no way to keep the fingerprint sensor always active. I understand it could be a battery drain or a security issue from accidental unlocks. But for those who want this feature, we without greatly appreciate a simply toggle option to keep the fingerprint sensor active while the phone is locked. Here is an older post about the same concern. /unlock-razer-phone-with-just-finger-print.32754/