When you press a Hotkey (1-9) in spectator mode with an Item on it (for example an Iron Sword) it (the Iron Sword) will appear in your hand.

What I expected to happen was...:
Nothing

What actually happened was...:
The Iron Sword appeared in my hand (not in first-person-mode)

Steps to Reproduce:
1. Go into Survival/Creative/Adventure Mode and place any item somewhere in the hotbar
2. Go into spectator mode
3. Press the hotkey (1-9) where you placed the item in game mode 0/1/2
4. Press F5 or E to see yourself.