Blocks/items will routinely do a slight "jitter" midair as they drop.

Steps to reproduce:

1. Break any block.
2. Look at the animation.

Observed results:
When blocks are broken, they sometimes jitter in midair before they land.

Expected results:
When blocks are broken, they don't jitter in midair before they land.

Original description:
When you break blocks, the resulting item always jitters in the air before falling.