Note

The exact reason why this happens is unknown. This bug cannot be reproduced in 1.9.

The bug

Having many hoppers (not pointing into each other) crashes the game. This crash is caused by a java.lang.NullPointerException (see attached crash report).

How to reproduce

Create a Superflat world with the preset

3;minecraft:hopper:0;1;

Description: Unexpected error

java.lang.NullPointerException: Unexpected error
	at aht.k(SourceFile:1415)
	at bcc.t(SourceFile:1642)
	at bcc.av(SourceFile:963)
	at bcc.a(SourceFile:393)
	at net.minecraft.client.main.Main.main(SourceFile:124)