Steps to reproduce:

1. Throw a few items on the ground (works with as little as 10)
2. Double-click the block the items are laying on as quick as possible with a lava bucket to destroy the items and remove the lava right after having placed it.

Expected behavior:

The items are completely gone.

Actual behavior:

The items that weren't destroyed are still there but appear invisible. You can pick them up by walking near them as if they were there.