Hi,
since one of the last two builds I sometimes run into the problem that my materials are being weirdly displayed in their thumbnail (very dark, also the shading ball background oddly). The textures are linked fine, but the thumbnail does not update when doing any changes, also when rendering every material is just plain white:
This happens to me exclusively with plugin textures, for example with the Greyscalegorilla Arnold Shader pack and the standard forester materials after converting them to Arnold materials.
Do you have any idea what might cause this?