=Sorry if my English isn't very good=

Sometimes if you fire an arrow it goes down immediately, even if you hold the right mouse button long.

I expected the arrow to fly long and high,
but it went down immediately.
You see the arrow going down, but it actually hits it's target and drops the item at that place.

It doesn't happen every time, only sometimes. But if it happens one time, it keeps happening until you quit & save. Also if it doesn't happen you have to quit and open the world again for it to happen.