Don't let passthrough turn off if you walk too far away from your play space.
I have have two areas I play VR in my house with Quest. A small one for seated experiences in my living room and a much larger one in my basement for room scale.
If I walk out of my small play space and walk towards my larger one the passthrough will just turn itself off and the screens go black. The default behavior should be never to turn off the passthrough for safety!