MC-96000Blocks that can't be placed will not return its drop.
Well here's how to reproduce it (the way I found out)
Get a wolf, make it sit down, attempt to place a block where it's sitting, and get no drop back.
2016-01-23, 02:34 AM
2016-01-23, 04:41 PM
2016-01-23, 04:41 PM
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