Capes in skin packs such as the 2016 Minecon Capes skin pack, the "Drone" skin in the Master Chief mashup, some of the Star Wars and Halloween mashup pack skins do not have matching Elytra, and often times the cape and elytra will just be straight up rendered invisible. Other times, the Elyta will be rendered properly but do not have matching skins. Whether or not this is intentional, it may as well be changed since it can occasionally occur that elytra won't render properly.