Invisibility mobs have some black texture on they head when the player in spectator mode

only applys to villagers since the "hat" is part of the model

but interrestingly the "hat" is also black if the villager is a farmer where the hat part of the model is used

Thank you for your report!
We're actually already tracking this issue in MC-164076, so I resolved and linked this ticket as a duplicate.

If you would like to add a vote and any extra information to the main ticket it would be appreciated.

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

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