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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It does not occur without FastChest. I can disable the mod in-game (it adds that feature) and the issue disappears.

Minecraft version: 1.18.1
Iron Chests version: both 1.5.3 and 1.5.4 seem to be affected, but I did not test older versions.

Can you confirm that the following bug does not happen without FastChest?
Also could you please provide more information such as:
-Minecraft Version:
-Iron Chests Version:

Thanks

Closing as FastChest's developer appears to not be maintaining FastChest anymore.