Apparently the Endermans manage to take an item found in the new Nether biome: Crimson Forest (I don't remember the name of the item, and it doesn't look like a block ...)

Thank you for your report!
We're actually already tracking this issue in MCPE-65399, so I resolved and linked this ticket as a duplicate.

That ticket has already been resolved, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.

If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.

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