Eseter

I recently installed the Aether mod. I accidentally started a world that was supposed to stay vanilla with the mod enabled. Now I can't open the world anymore without the mod enabled even though I didn't use any new blocks or oher content from it in the short time the world was loaded. I also tried to delete the aether folder in the save. It works then but resets the seed completely and all my builds are gone then. I already asked on the Aether Discord about this but they claimed it's a Forge problem and redirected me here.