This has probably been covered, but I couldn't find any information through the search. Basically, in the creative and survival inventories, the texture for colored Shulker boxes are bugged. More strangely, they are textured to the white box (rather then the spawning purple box). Is this a bug or perhaps is the texture not implemented. It is worth noting the in-game placed and holding textures work fine.

Steps to Reproduce
1. Open the creative inventory.
2. Tap the bookshelf icon.