I thought shipwrecks were suppose to be at the bottom of the ocean... Apparently not.
MC-129695
Shipwrecks spawning above water
Resolved
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0
Spooncer
(Unassigned)
Unconfirmed
Minecraft 18w20a
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I bet it is intended XD
See the changelog on https://minecraft.net/zh-hans/article/minecraft-snapshot-18w11a:
[media]Still, shipwrecks found near beaches IRL are not that weird.