Using the old materials, not PBR materials, some textures with transparency do not render using the PBR viewer.
Half of my clothes appear invisible because they have transparency, so I cannot use them.
Walls with transparency are invisible to me, though I still bump into them. So anything like handrails, windows, fences, are just invisible.
Banners with some transparency, for example in voice island, I cannot see the banners.
No prim water either, so no ponds and fountains.
At the moment I am using firestorm without PBR to be able to view my clothes and walls.