The bug
Two tall flowers are only one block tall because of tree generating.
How to reproduce
Seed: -8534830376248092263
Coordinates: /tp -2044 67 -1763
Related issues
Attachments
Comments

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Confirmed in 1.13-pre3.
However, it is no longer present in the given example.
It is also important to note that small flowers will also destroy tree leaves.

Duplicate of MC-610