When in a swamp (It doesn't have to be a swamp though) and you break all the logs from a tree, the leaves will start to decay naturally, but when the leaves that have vines on them decay, the vines stay floating. This glitch has not been fixed, even though MCPE-13517 was fixed, and they are basically the same glitch.
I am unable to reproduce this in 1.16.40.
If you are still experiencing this issue, please tell us what kind of biome and what species of tree the vines were attached to. Before and after screenshots would be especially helpful, as it might be only vines that are attached a certain way that are affected.
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