WebCamTexture.devices.Length returning 0 in Unity 2020.3.8f1

I run my code on Snapdragon 855 Mobile Hardware Development Kit and call "WebCamTexture.devices.Length" to find the camera device number , but it always return 0 in Unity 2020.3.8.f1. However I change unity version from 2020.3.8.f1 to 2019.4.8f1, I can get the correct camera number. How to solve this problem in unity 2020.3.8f1?

environment: unity 2020.3.8f1 Android SDK 9.0 (API level 28)

device: Snapdragon 855 Mobile Hardware Development Kit,I run my code on Snapdragon 855 Mobile Hardware Development Kit and use "WebCamTexture.devices.Length" API to find the camera device, but it always return 0 in unity 2020.3.8f1. However when I change the unity version from 2020.3.8.f1 to 2019.4.8f1, I can get the correct camera device number.

Environment: Unity 2020.3.8f1 Android SDK 9.0 (API 28)

Device: Snapdragon 855 Mobile Hardware Development Kit