Walls only connect to one side of a corner stair block.
HOW TO REPRODUCE:
2x Wall block (any type)
3x Stair block (any type)
Place the walls in a corner shape.
Place a stair block in between the walls.
Use the 2 other stairs the make the center stair a corner stair.
If reproduced correctly, the wall should only connect to one side of the corner stair.
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We're tracking this issue in MCPE-87311, so this ticket is being resolved and linked as a duplicate.
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