As ticket http://feedback.arma3.com/view.php?id=11064 has been closed ....

It's not fixed and it's not trivial. Just nobody at BIS did take a look at this ticket. The inventory design of A3 is awful when it comes to filtering.

Currently you can only filter between
a) weapons
b) magazines
c) items
d) all

Backpacks are listed everywhere which is very annoying. A similiar filter like being used in the virtual ammo box would be nice. {F24592}