when zombie is transformed to a drowned, he drops all his items with full life.
to replicate this bug:
first, find a zombie with armor or a hand item.
second, put the zombie head underwater and keep on until the zombie is transformed in a drowned.
then, you can see all zombie items near the drowned with full life.
Linked issues
Comments

Thank you for your report!
We're actually already tracking this issue under MCPE-33140 so I've requested this report be resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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