I recently had an issue when entering certain chunks caused a massive lag spike, freezing the game up to several seconds.
After trying to find the source of it, I along with fellow players concluded that the source of the lag spikes were a set of playerheads which had the names of non-existing players.
Simply placing or removing these heads on their own would lead to great stuttering.
and the presence of several within a set of chunks would then always lead to the game freezing for a moment when loading set chunks.
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Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-65587, which is a report that has not been resolved yet.
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