Tab does not close inventory

I remapped TAB to my inventory close/open key. TAB will open the inventory, but the inventory screen will not close.

What I expected to happen was...:
The inventory screen should close when I press TAB in the inventory screen.

What actually happened was...:
The inventory screen stays open when I press TAB in the inventory screen.

Steps to Reproduce:
1. Rebind "Open/close inventory" to TAB
2. Press TAB
3. Press TAB again to attempt to close inventory screen. This will not work.