Random blocks generating / replacing the terrain on existing chunks

The bug

Random blocks (usually dirt / grass / air) begin to generate and replace parts of the terrain in alredy generated and saved chunks

How to reproduce

• Create a new world (preferably with the following seed: -6352910936363096162)

• Observe the surrounding terrain
  → ❌  Notice the trees, leaves, vines, bamboo begin to fall apart and get replaced with random blocks from the ground