I test the the Passthrough feature on Htc ViveXR, if i select the [Mobile Multi-View] in project setting . if I run apk in ViveXR ,I show Passthrough Underlay, the background will be the black screen .
Dev tools: UE 4.27
WaveSDK: wave_5.1.1-r.4_UE_4.27
Device: Htc Vive XR