Fuel tooltip
My suggestion:
Do the same for ammo slot, i.e. add tooltip to show the acceptable ammo, just like this:
Ammo tooltip
Missing such tooltip isn't a big problem for vanilla game since there isn't much ammo types. But this would definitely help modded games with more ammo types.
Edit: oh, I missed the ammo slots on the tool panel (the one at bottom left now). I imagine the acceptable ammos would show up for the ammo slots that have weapons above.
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