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Взаимодействие с другими людьми
Well, it is impossible to type //undo in console though. But check your world again, maybe there is chance that your world didn't save. If it does, there's nothing you can do to fix it.
You can use this plugin if you want to paste large builds: https://aternos.org/addons/a/bukkit/fawe.
Ok, but can I somehow use .schematic files from computer on server?
I ran into one big problem. The fact is that, using the // set command, I replaced the entire building with a stone (somehow it happened by accident). But the server did not have enough RAM and it turned off (the building was large) 
. Can I undo this action through the console?
PS Sorry for the bad English, I don't know this language and I used google translator...
