you can shoot down every door that it's not a transition door (eg. between districts). I don't know if they let it slip or it was intentional, but if the door is locked/is hackeable you'll only know the strength after you unlock it. when a door is put down it'll warn nearby characters, so you've gotta be careful. it's like crates, when you move your reticle over it to interact, it will show how hard it is to break it...
and yes, common ammo in the inventory is ridiculous, and also the stacking is also dumb. I understand they MIGHT want to limit grenades, but I could just cheat myself with mines if that's what they want
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