Iron Chests for Fabric's chests can't be rendered as static blocks, which is what FastChest does. It looks like Minecraft tries to render the chest both as a dynamic models and as a static one. I'm not sure which mod is responsible.
I fixed this on the FastChest side now, to make them rotate properly I'll also have to get some changes to the block state jsons merged into Iron Chests.
Iron Chests for Fabric's chests can't be rendered as static blocks, which is what FastChest does. It looks like Minecraft tries to render the chest both as a dynamic models and as a static one. I'm not sure which mod is responsible.
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