When an ender dragon is summoned it lacks hitboxes for a single tick and as such can't be interacted with. The sub-hitboxes are located underneath the portal, at 0, 0, 0.
Steps to Reproduce
Do /tick freeze
Summon an ender dragon
Step 1 tick
Observed result
When the ender dragon is summoned it lacks hitboxes
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After stepping 1 tick the hitboxes appear
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Expected result
The hitboxes would appear immediately after a dragon spawns.
Linked issues
duplicates
Attachments
Comments

Considering how similar the issues are I think this info should be added to MC-252478 and this should be marked as a duplicate
I will go ahead and confirm the report instead of resolving as a duplicate just in case. I'm not confident enough to resolve this into MC-252478 and then broaden that report. Considering the gameplay impact is also different as well (this instance is very minimal, only for one tick. The other case is for as long as the dragon is alive).

It's definitely the same: ender dragon sub-hitboxes are positioned at 0 0 0 until the first AI tick; whether AI is disabled or not, it's the same problem
In that case it can be resolved as a duplicate.
This issue appears to either be the same, or have the same cause as MC-252478. The hitbox is located at 0 0 0 before it is later moved.
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