If you use "Pick Block" on certain items (listed below) in the creative inventory to duplicate it, after switching to survival (via /gamemode s), all except the last cloned item either turns into an "infinite item" or a ghost item when you start using them.

Steps to reproduce:

1. In creative mode, put an item to the first slot of the hotbar.
2. Use "Pick Block" on the item to obtain a duplicate.
3. Put the duplicated item to the next slot.
4. (Optional) Repeat steps 2 and 3 a few times.
5. Switch to survival mode /gamemode s.
6. Start placing or using the item and now you either have an infinite item, or it simply disappear and do nothing.

Behaviour of infinite item:

• You can place the block/Minecart infinite number of times.
• When dropped and attempted to be picked up in survival, it fills up your inventory infinitely.
• When dropped and attempted to be picked up in creative, it turns into a ghost item.
• When put into a dispenser/dropper, it can be dispensed/dropped infinite number of times without being used up.

Items that will turn into infinite item (incomplete):

• All types of Minecarts
• Doors
• Splash potions

Items that will turn into ghost item (incomplete):

• Boats
• Splash potions

Note: The bug with splash potions had been reported in MC-9361, but the behaviour is inconsistent, i.e. sometimes turns into infinite items while sometimes turns into ghost items.