Framebuffer is incomplete: Attachments are not all the same size.#97

Using `PostProcessingSprite()` sometimes the sprite just doesn't get rendered. It's than throwing these kinde of errors:  I'm not using any textures on the 3d model, so it seems like it's talking about the PostProcessingSprite itself as being a texture. I believe I've seen other people with the same error message on the pixi github, but I can't find it nowhere anymore and even then to me and I believe also to them it was completely unclear what was causing this and how this could even be worked around. I'm trying to debug this at the moment. Any clue on what could cause this issue to happen? Could it be related to using the PostProcessingSprite's `resolution`, `width` or `height` settings? Does this even have anything to do with textures? Or could it even be something else completely?