In a multiplayer world we came across a mineshaft with three cave spider spawners near each other, however the flame particles of the cages were greatly increased in number, to the point where you couldn't see the mob in the cage, and most of it was covered. As far as I can tell, there is no distinct way of triggering this bug, it is just a visual glitch.
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However, this issue has been closed as a Duplicate of MC-137732.
It has been linked to this report. If you have additional information, please add it to the duplicated report.
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