I have encountered several worlds where biome chunks rearrange themselves in EXPLORED territory. My newest world suddenly appeared at the bottom of my world list with the name deleted and upon entering it there were random mesa square chunks everywhere and chunks completely removed.

This is an ongoing issue for me with multiple worlds so I know it's not just me. Though the game is playable, it is pointless if all my work is constantly destroyed by terrain gen.

Also I would take screenshots but the win+alt+printscreen isn't working. So here's a quick vid.