I'm trying to assign a second material to top and front faces (using 'assign' button in the material collection, as explained here). But instead the faces become transparent:
They are transparent in the preview and in the rendering as well. If I remove the second material from the collection (slots?), the faces are visible again.
Things I did:
- Reinstalled Blender to be sure.
- Swapped materials for faces, faces with material from slot 2 are transparent regardless of material in slot 2.
- Added a third slot, and linked faces to random slots. Slot 1 always work, other work randomly, not always the same which work.
Using Blender 2.81a, with a default new scene, cube and default material except base color.