I have been playing on a world for a couple of months now. All of the sudden, I've found that the world now reverts to the original world state whenever I save and exit. The only things I retain are my current inventory, toolbar, advancements, statistics, current location, and levels.
I have no idea why this is happening, though it appears to be similar to MCPE-42226 from the Bedrock edition.
Judging by the report linked and the save files below, steps to reproduce might include:
Start a save
Travel throughout the world to increase save size (files approximately add up to 164 MB, so attempt to get to that)
Build something and keep items in your inventory
Save and quit to title
Thank you for your report!
However, this issue has been closed as 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, such as The Hive and Hypixel, please contact them first as they run modified server software.
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