I Cant Load My Old Worlds In The Snapshot Apparently.
I Cant Even Create A Backup Of The World And Load It
Its Very Annoying As I Have Most Of My Worlds In The Latest Release And I'm Playing A lot In The Snapshot. I Would Be Extremely Happy If You Fix This Glitch Or Email Me How To Fix It If It Isn't A Glitch. Thank You For Taking The Time To Read This.
Henrikas
This report appears to be a duplicate of MC-214806, which was later resolved as, "Works As Intended". You are experiencing this issue, as the world height + depth has changed as of snapshot 21w06a. Please see the parent ticket for further details, regarding this problem.