I have experienced an issue with the Shedu where it seems to be random, but I will completely lose the ability to fire the weapon. I have tried the unstuck command, swapping weapons, and dying to fix it but nothing seems to outside of leaving the mission. The gun will simply not fire, it wont play an animation or anything. It just does nothing when you click to fire. Its not out of ammo, it is still at full ammo.
I have played several missions as limbo prime, and have had several situations where I am unable to use 1 to rift enemies as they say unavailable target even when in range, times where enemies do not take damage or react to being attacked either in the rift or not, and being unable to banish enemies into the rift while I myself am in the rift.