Moving a Composter block back and fourth quickly enough will permanently lock it in whatever level it is in.
Even right clicking with a compatible item on the Composter block will not do anything.
Mumbo Jumbo pointed out this bug when he was exploring the red stone purposes of the new block.
https://youtu.be/Oo1VDtH002g?t=342
At 5:42 this bug is shown.
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However, this issue is a Duplicate of MC-142568.
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