Basically this pasted command corrupts chunks when run:
summon falling_block ~ ~1 ~ {BlockState:{Name:"minecraft:redstone_block"},Passengers:[{id:"minecraft:falling_block",BlockState:{Name:"minecraft:activator_rail"},Passengers:[{id:"minecraft:command_block_minecart",Command:"tellraw @a [\"\",{\"text\":\"[\",\"color\":\"white\"},{\"text\":\"魔法] \",\"color\":\"white\"},\"プレイヤー: 天つ日よ、我が呼び声に応えよ。大地を照らし、邪悪を滅ぼす一閃を放て.\"] \n execute as @p at @s at @e[type=monster,distance=..15] run summon lightning_bolt ~ ~ ~ \n setblock ~ ~-1 ~ air \n kill @e[type=command_block_minecart,distance=..2]"}]}]}
When you upgrade the version to 26.3 it will give an error and if you downgrade it back to 26.1.2 the surrounding chunks will disappear or reset (Im still not too sure the conditions to get each result but one world is superflat and one is normal chunk generation)
Environment
Allow Cheats, Java Version: 26.1.2
Attachments
Comments 2
This issue is invalid. Your game is modded, and in any case only issues which occur in the latest release version or development version are valid, meaning world downgrade bugs are not valid unless you are attempting to open a world from the current snapshot cycle in the latest release (which the game will not allow under normal circumstances).
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