I saw something like this about a cow landing into a block when riding a falling_block. However, this is an important issue because when a falling_block lands with others on top of it, the ones on top will pop off. This makes one command creations in 1.14 impossible, meaning this needs to get fixed before the 1.14 full release!
Linked issues
Comments 2
Duplicate of MC-145113 (covers all entities, not just cows)
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