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21w37a introduced new culling but this incorrectly filters chunks in a certain scenario as seen in the video above. Looks like "inverse" culling. This happens when not all chunks are loaded or when near the edge of currently loaded chunks. You can reproduce by flying quick, spectator mode and scrolling to increase speed makes this easier to reproduce, but this also happens in creative.
High similarity with MC-166508, this is a duplicate!This is not!