What I expected is it to render a chest model where the falling sand entity is. This did not happen.
What happens:
Entity DOES fall
Shadow DOES render
Entity DOES land creating the correct block
Entity DOES NOT render the chest whilst falling
I am pretty certain this has to do with the fact that it would be rendering a "complex block model", and Mojang either overlooked it, or decided not to implement it.
I know in earlier versions it would render an oak plank block, as that was the default texture assigned.
Maybe this is intended, maybe not, but I do think that chests should show as they fall. I see no reason why they shouldn't.
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duplicates
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I'd say this is technically a duplicate of MC-64634 - just need to add chest to that report.