Clicking Alt-LeftMouseButton on an item in the inventory is supposed to put all of that item to storage. This doesn't work on my system with the standard Alt key to the left of the keyboard. Instead I have to click the AltGr button, which is to the right of the spacebar on my German keyboard. Strangely Alt works for other commands, such as Alt-s sit/stand.
I had a look at the key.ini file, but can't find any likely settings that might affect this.
System information
I am running on Debian with the package version 1.9.5.8-15debian1.
The setxkbmap command gives the following:
setxkbmap -query
rules: evdev
model: pc105
layout: de
variant: nodeadkeys
I have not altered my key.ini settings.