Place a chain sideways (iron chain or any copper chain version). Attempt to place a cushion on it. The cushion insta-breaks.
(note: The cushion can successfully be placed on sideways end rods and lightning rods, and in the Java snapshot the cushion can be placed on sideways chains)
Thank you for your report!
However, this issue has actually already been reported in MCPE-240466.
The issue goes deeper! Chains will break any cushions placed within the same blockspace, regardless of orientation.
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