Player's rotation displayed in f3 window is different from the rotation that the /data get -command gives. See the pictures below.
I used the following command:
/data get entity @s Rotation[0] 1
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Player's rotation displayed in f3 window is different from the rotation that the /data get -command gives. See the pictures below.
I used the following command:
/data get entity @s Rotation[0] 1
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Minecraft 18w14b
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It not the F3 menu that's wrong, it's the NBT, see MC-121855.