After logging out of my world I am no longer able to play on it. When it loads it crashes.

Put the summary of the bug you're having here
The game would not let me launch my world save. It would try to load and then crash.
What I expected to happen was...:
Describe what you thought should happen here
I expected to be able to load up my world.
What actually happened was...:
Describe what happened here
When trying to load it crashes and closes the browser.
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...Launch world.
3. ...Wait.