When entering a server right after starting the game, a game crash occurs

What I expected to happen was...:
Game should load and player character should spawn like usual

What actually happened was...:
After the "Logging In" screen disappears, the window turns black and crashes. See attached Crash Log

Steps to Reproduce:
1. Start the game in 18w07c
2. Click "Multiplayer" and try to enter a server running the version
3. Take note how short the "Logging in" screen appears