All upright shipwrecks in the world appear to be generating incorrectly across chunk borders, with half of the ship made of a different material and one block higher than the other. Specifically is happening on seed 344131611190769990 at coords 1651 -7872 and other shipwrecks in the same seed.
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We're tracking this issue in MC-131745, so this ticket is being resolved and linked as a duplicate.
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