Items dropped by entities take one tick to appear

The bug

After an entity dies, its items take exactly one tick to appear, instead of properly appearing instantly.

How to reproduce

Set up these command blocks:

1. summon pig
2. kill @e[type=pig]
3. kill @e[type=item]
 
Press the button
→ Pig's items were left behind

Now modify the final command block to have a tick delay of 1, and try again. This time the items were successfully deleted. Note that this workaround is unacceptable as a permanent solution due to the fact that functions cannot be easily delayed in Bedrock edition.

Note

Blocks that are destroyed properly drop items immediately.