@ bewoi and Bilbous, yes I know this 'shortcut' .... thank you for saying, and it does save time. However, what I want to do is simplify even further, with "unstack", a single-click, rather than 12, or 10, or whatever number into the
container: the actual reverse of the "stack and take all", which goes to inventory. Shift-clicking can be extremely wearisome on the fingers ....
especially for something like metallurgy, for example.
@ cdmoreland, I agree with the annoyance of characters filling the entire container, I have had that happen to me. I either wait, or go somewhere else, or just put in 4-8 materials (when I can). I have also had the happy experience of the other character saying "I only need 12 (or whatever number) spaces. Can we share?" and that works well too.