Nether Portal crash - urgent fix required

Upon exiting the Nether to return to the Overworld, the game will remain on the loading screen that re-renders the chunks. The game will freeze and not change screens at all upon entering this loading screen, and causes the game to crash. This is a major bug in the current snapshot, and must be fixed whenever possible so that players can fully enjoy the dimensional travel between the Nether, the End and the Overworld.