Apparently there's a fix, that was made in ST#53, to stop you from shooting yourself from moving.
But it causes an issue, not sure if intentional, but this is bad design.
That's when you are moving while shooting, (in regular stood up stance, crouching stance, and even prone stance.
If I'm moving while I have my gun raised, I can shoot, **but if I'm using SHIFT at all, You can no longer shoot.**
This is a big problem, because by habit, and for many others, we may be having our gun raised, and holding SHIFT (by habit, because naturally we want to move faster), we will try to shoot, and nothing will happen.
Possibly resulting in salty deaths, and anger, so an issue that needs to be considered.