This conic shape appeared near coordinates 328/70/610. Looks like world or chunk border, but more dense.

I suppose it filled the chunk on the last screenshot (or the first one, I don't know the order in which the files will be attached here, it's the one with chunk bordes)

It was visible only from the specific spot from the distance. It appeared only at a certain angle too.

1.19.4 vanilla
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