If the wandering trader drinks a invisibility potion, and Show Hitboxes is set to On, his hitbox disappears.
HOW TO REPRODUCE:
Press F3+B;
Summon a wandering trader;
Run the command: "/time set midnight"
The wandering trader should drink a invisibility potion, and his hitbox should disappear.
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Isn't that the case for all mobs with the invisibility effect (players included) so that players can't cheat by turning on visible hitboxes (which would let the player see said mobs)?
Affects all mobs, this is WAI because of MC-4069.