I've been testing this bug thoroughly the last few days,
The Symptoms are basically the following :
- Can't Vault
- Can't Open Doors / Interact with anything that uses the pop up interface thing.
- Can Use inventory BUT It does not update on the client side.
- Can't Equip a weapon (unless it was equipped before the bug initiated)
Reproducing is a bit of luck but typically easy (for me, and apparently many others looking at the thread provided below)