Minecraft wiki entry for Unused_textures, associated text: Interestingly, in Beta 1.9 Prerelease 5, despite being completely unused in-game, this texture was actually changed alongside other block textures that changed in this version. The actually used grass block texture also changed in this version, however despite both textures being identical beforehand, the Beta 1.9 Prerelease 5 textures made the two textures visually distinct from each other.