Put the summary of the bug you're having here
For some reason, when I save and exit occasionally my world does not save in single player, no mods. My inventory saves and my location but some of the blocks that I placed or removed gets reverted back to a previous state (rolled back) or items that I took out of a chest appear back in there even though they are in my inventory as well, effectively duping the items. Reversely if I put items in the chest, I lose them permanently because they are no longer in my inventory and the chest rolled back to a previous state. Auto-save appears to work for the most part but this happens only occasionally.

Its hard to duplicate because I never know when its going to happen

Twice now I have had chests "roll back" to a previous state losing some of my valuables.

What I expected to happen was...:
My game should save like it is supposed to.

What actually happened was...:
Game file "rolls back to a previous state", although its never too long, usually never more than say 5 minutes of in game "building"

Steps to Reproduce:
1. Your guess is as good as mine (hopefully better)
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