undo question

[Element]

i have done something stupid, i tried to open two windows for one world but with different ports and now my world is messed up, is there a way to undo the change

[rubenwardy]

depends. Only if the file is not corrupt.

see /rollback

[sfan5]

I did sth like this, too, and used a backup.
mt thinks the world isn't generated yet and removes my buildings

Minetest doesn't think anything, if there is no MapBlock where you are with the player it generates them