When I place a painting it does not show up in the world. This happens for paintings that were placed before the update too. I have no texture packs on my world at all so it cant be one affecting it. They still are placed and can be destroyed but they are invisible. This does not happen with any other block as far as I know. I will update if I find more. I asked my friend if she has this bug and she said no. She has both nintendo switch edition and pocket edition and told me she didn't have the bug on either.