Can't delete all textures

I am creating multiple models using simplify and filtering. The models created all have textures, color and normal, which I think are increasing my file size and slowing down project saving. On each model I can delete one texture, either color or normal, but after I have deleted that one the remaining texture can no longer be deleted. Is this a bug or something to do with deleting the UVs?

RC v 1.2.017385


Hi Steve, it is not possible to delete one created texture. It is possible to delete just if you have created more textures.