Put the summary of the bug you're having here

What I expected to happen was....
I expected all of my items to be exactly where I left them in my chests, inventory, dispensers, etc.
What actually happened was...:
Everything in the chests, my inventory, dispensers, hoppers, etc. disappeared after I switched versions.
Steps to Reproduce:
1. Open Minecraft launcher
2. Go to edit profile and switch your version to a recent snapshot
3. Click save profile and start the game
4. Mess around on the snapshot – any world
5. Exit the game and start the launcher back up
6. Go to edit profile once again and change your version back to the current official version
7. Save and start the game again
8. Go on any world (it does not have to be the one you were on earlier)
9. You will then see that all of your items have disappeared from where they were stored
5.