Random and rapid display of repeated sections of blocks from different areas of world after saving and quitting to title and loading save game or starting new world.

Put the summary of the bug you're having here

What I expected to happen was...:
After leaving a world by saving and quitting to title and then starting a new world or loading a saved world, the world should appear normal.

What actually happened was...:
The newly created or reloaded world rapidly flashes a series of repeated groups of blocks. Breaking a block will stop flashing until head direction is changed with mouse. Seems to affect all 1.9 snapshots tried on this PC.

Steps to Reproduce:
1. Play in 1.9 pre-4
2. Save and quit to title
3. Either load a save game or create a new world
4. Watch screen go crazy