This bug has appeared since sometime in the 1.9 snapshots and has since not been fixed, even in the latest snapshot. I'm not sure of the cause; it could be a problem that has something to do with resource packs and the new 1.9 sounds making them incompatible, but I'm not entirely sure.
Steps to reproduce:
1. Open up Minecraft PC.
2. Load or create a world.
3. Go back to the main menu.
4. Load that world again.
5. You should notice a visual glitch where blocks keep flashing all over the place.
Some images:
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Please force a crash by pressing F3 + C for 10 seconds while in-game and attach the crash report ([minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt
) here.

There's no crash involved.

You should be able to reproduce the glitch easily anyway.

I put up the crash report now. First time I ever had to force a crash.

I'm not asking you for a crash that happened, I'm asking you to force the game to crash. I suspect the issue is graphics driver related, since this is not normal behaviour, and I want to diagnose that with said crash report.

Yup as expected. Duplicate of MC-62958. This issue is caused by broken or outdated AMD graphics drivers. Please see that report for details.

Just a quick note that this works on the default world type aswell. I'm on amplified, but it works on all world types.