Java Edition 13w21b

13w21b is the ninth snapshot for Java Edition 1.6.1, which was released to fix some of the bugs and crashes in the 13w21a snapshot.

Fixes
7 bugs fixed

From released verisons before 1.6.1
 * – Certain death message will print "null" as the player/mob name that caused the death.
 * – lang files for en_US is grammatically incorrect at death.fell.finish.item.

From the 1.6.1 snapshots
 * – Enchanted items stored in a donkey / mule lose enchantments on its death.

From the previous snapshot
 * – Sprinting and speed effect not working.
 * – Server doesn't translate strings.
 * – No sounds after a while/music corrupting sound.
 * – Crash: IllegalArgumentException.