I found this bug while testing to see if MC-85910 still affected 1.19-rc2.

How to reproduce:

Run the command: /summon ender_dragon ~ ~ ~ {NoAI:1b}

Expected behaviour: the dragon's body part have hitboxes

Actual behaviour: the dragon has only one hitbox covering the whole thing, but that hitbox can't be hit or anything, it's intangible 
(in the image there's 2 ender dragons, thats why there's 2 hitboxes. the second is covered by the first)