Adding items by selecting content in crate

[Wyqer]

Suggestion/Feature request

Is your feature request related to a problem? Please describe:

Imagine you pack a crate with some ammo from different weapons or let your squad mates put one magazine of their weapon in a crate, so you can see what they need.
Now you open the cratefiller, select the crate and also see the content with the different magazines. But sadly you can't click on something in the content list and add more items, you have to search the weapon to each magazine and add them from the left selection menu.

Describe the solution you'd like:

It would be more user friendly if the "item adding" recognize if you've selected something in the left or in the right list and use this selection as reference for adding something to the crate. So basically that you can't just remove something, but also add something when selecting something in the content list of the crate.

Additional context:

Nothing