Filtering Hoppers

I realized after messing around for a tad longer after I released 1.2.3 that there was a massive issue. Due to the way Paper works internally with hoppers, the issue described below would occur.

• Fixed a critical issue that erased entire stacks of items if they happened to be in the filter and the first item in the inventory

I only now exited the tunnel vision I was stuck to after resting for a while, I'm terribly sorry that an item loss bug was out in the wild for so long