Blocks dropping items from inventory, even when not supposed to.

Status
Works as designed
Issue description

I'm working on a combination lock where you put in different items into it to be the combination. I have it set not to drop items out of the block's inventory, but it does anyway. Obviously, this kind of defeats the purpose (why would anyone want a password that's erased as soon as they set it?). Any idea why this is happening?

The block is CombinationLock.

Issue comments

The slots if your GUI are bound to custom inventory. This inventory is GUI specific so the items need to be dropped after the GUI is closed as they can not be stored anywhere.

You need to bind your slots to the inventory called inherited, which is the inventory of the block you bound the GUI to. In such case, items are stored in block after you close the GUI and they won't be dropped.

I thought it might be something like that... any insight on why there are four inventories called 'inherited'? (Well, there were last time I checked. It may not have this problem now... Would you mind answering this problem as well in case it happens again?)