It happened many times. And I died from a zombie and all my stuff disappeared instantly. I know there's a time limit before your stuff disappears but they disappeared right after I died. One time a player was next to me when i died and even though I literally had my inventory full, nothing dropped. The command "keep inventory" was off (if this helps) no cheats enabled.
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We're tracking this issue in MCPE-121025, so this ticket is being resolved and linked as a duplicate.
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