I discovered this while crouching under an upside down stair, went into third person, didn’t see anything. I didn’t test an actual slab but I can imagine it’s probably the same, let me know if otherwise.
This feature of sneaking under slabs, or under 1.5 block gaps was just recently added in the 1.20.10 update so I’d thought I give it a try, but then discovered this bug.
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