The Zombie Piglin Chicken Jockeys do not despawn. Over time the nether fills up with Chicken Jockeys. I noticed it after making a gold farm on the 20w18a snapshot and after being AFK for a while there were just hundreds of chicken jockeys. The chicken jockeys would not despawn even after the player is more than 128 blocks away.
Thank you for your report!
We're actually already tracking this issue in MC-182308, 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.
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