This sounds stupid but I really haven't found any way to benefit from the foreground/background color setting

Manual says nothing about it and I have tried many ways but only thing I can do with it is to select a color or pick color from Clarisse Image/Texture etc. into it but how can I then use that color anywhere?
I thought that when I have color dialog open, I can apply the foreground color to it by clicking the foreground color button but actually it only opens new color dialog and hitting ok there does not affect the color I was adjusting (it only changes the foreground color).
So please tell me how can I use the foreground color in items' color attributes?
There must be some trick but I haven't figured it out

Thank you
