Whenever a block changes, the chunk re-renders; this is fine normally, but when blocks change several times in 1 game tick (eg redstone wire turning on/off); it re-renders every single time a block changes, even if another block changes afterwards in the same tick.
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McModknower
migrated
Possible fix concept: add a boolean to every chunk if it should re-render and execute the re-render after everything else in the tick has happend so multiple updates in one tick would only re-render the chunk once.