Jamie

Added report using official launcher.

Update: The crash seems to trigger on clicking an item, not just shift-clicking it. Attempting to move a shulker to my inventory crashed the game. I had just disabled all datapacks except [minecart-improvements] as well, so disregard those in the crash report.

After sleeping on it I realized that VanillaTweaks' “More Mob Heads” datapack changes mob drops. After disabling that through commands, the issue was resolved.

What threw me off was that (1) the world this issue came up in did not have any mods or loaders present for the prerelease 2 version and (2) I didn’t think that the datapack rewrote mob drops, only added the chance for a head drop.

I was just made aware that MC-279245 exists and has been closed! Apologies! Thank you all for the hard work you do!

I've been having the same exact issue, except its when I load any world with the C&C Datapack.
I've attached my crash report, as I believe this is the first issue opened on this crash. 

I am so stupid thank you

In the soul sand one i made it all source blocks yet it doesn't make me go up, but the magma one makes me go down.

UPDATE: I fixed it by opening the GeForce Experience app and updating my graphics card's driver to the latest version. I think you can do this on the Nvidia website if you don't have the app.

Sorry!! And thank you so much 🙂

Well, here's the decompiled code from MCP to fix this in 1.9, for Piggies anyways.

public void onDeath(DamageSource par1DamageSource)
{
boolean flag = this.worldObj.getGameRules().getBoolean("doMobLoot");
if (getSaddled() == true && flag == false)
{
this.dropItem(Items.saddle, 1);
}
}

Yep.

I placed the yellow on the duplicated and the red in the same spot on the originals, and when I reloaded they had disappeared.

The world folder is 486 MB when compressed and I can only upload up to 10 MB. What should I do?

these are the best pictures I have of the bug

Yeah, similar issues except I wasn't mounted on mine it was just within a few blocks of me.

Yes I can confirm this does this in 8.0

I used to get this intermittently (once per session), switching to another app then switching back used to solve it. Since the 1.4.7 update it happens every minute or so rendering the game unplayable.

Minecraft 1.4.7

Java(TM) SE Runtime Environment (build 1.7.0_11-b21)
Java HotSpot(TM) 64-Bit Server VM (build 23.6-b04, mixed mode)

ProductName: Mac OS X
ProductVersion: 10.8.3
BuildVersion: 12D54

Since the problem, I had my amazing friend come I've, and she managed to solve this issue. What she did, was go to .minecraft, and then she deleted jar. When we tried to go back on minecraft, it automatically downloaded the new jar, and I could play minecraft normally again.