As of now, Shulker boxes can open with a top-sided slab above it. But when a Shulker box is upside down with a bottom-sided slab below it, it cannot be opened. This is not an intended feature.
MCPE-136487
Upside down Shulker Box Opening Bug
Resolved
Duplicate
0
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We're tracking this issue in MCPE-38467, so this ticket is being resolved and linked as a duplicate.
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