In 1.21.4 and earlier versions, you can use bonemeal on pink petals which has a flower_amount less than 4 to grow it, and let it drop a pink petal item when it has a flower_amount at 4.
However, this was changed in 25w02a.
Steps to reproduce:
Put a single pink petal or wildflower on ground.
Use some bonemeal on it.
Excepted behavior: The block should grow one more, just as in 1.21.4.
Actual behavior: The block directly drops an item, even if it hasn't grown fully.
In the source code (decompiled, Mojang official mapping), the method performBoneMeal the FlowerBedBlock class, the if statement "i < 4" was changed to "i < 1". Apparently this will never be true, so the behavior of growing is skipped.
In addition, this behavior is only changed in Java Edition, and not in Bedrock. And the change is not mentioned in the change log. So this should be regarded as a bug.
Can confirm.