So..from what I can gather, QS-Inv doesn't seem to be updating the client cache of the players inventory correctly
This is all speculation, I can't check this myself
When `hasItem()` is used, its essentially reading from the client's cache.
This seemingly is only updated when there is a new item in a slot, **not** when the amount of an item in that slot changes
The only way to circumvent this is a workaround to the players inventory from the server side using a callback. This is painful to do because it can increase server load when checking multiples of items
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