I was opening up Minecraft to play my new vanilla world I've put a couples days into when for some reason the world wasn't showing on the selection screen. The files are still there but I don't know why its not showing or how it could've been corrupted.
Thank you for your report!
However, this issue is Invalid.
Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.
Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.
Any plugin issues need to be addressed to the creator of the plugin or resource pack.
If you have problems on large servers like Hypixel, please contact them first as they run modified server software.
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