It might not be bug, but just in case, I was building in creative mode and I middle clicked Azalea Leaves to get Azalea Leaves but instead, they given me Azalea, not Azalea leaves, and same for Flowered ones.
(I tried to upload videos but I couldn't)
Thank you for your report!
We're tracking this issue in MCPE-128092, so this ticket is being resolved and linked as a duplicate.
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