I've run into a strange issue where using a lambda to implement ItemMeshDefinition crashes the game with an AbstractMethodError any time the item is rendered in a GUI. This only happens in the obfuscated client, not in the development environment.   I've set up a small test case here. The lambda is used here.   To reproduce, simply open the mod's creative tab or spawn in its block. The block will render without issue in the world, but as soon as it's rendered in a GUI or a player's