If you hold a unused tool and go through the nether portal to the overworld the game crashes when you get back in the world the tool is used. If you do it alot your world wont show up when your trying to select it when your in the singleplayer menu

I go through the nether portal and into the nether and when I come out my game crashes and my world wasnt able to be showed on the "Select World" screen

What I expected to happen was...
nothing to happen my game just keep playing like it used to in previous updates

What actually happened was...:
my world didn't get deleted but wasn't able to be shown on the Select World screen

Steps to Reproduce:
1. Go to the nether
2. exit the portal in the nether
3. Get back in the portal to go to the overworld
4. The game crashes
5. If you do it continuously do it the World wont be deleted it just wont show that it is in your save File.