Sometimes I lose the parts I insert into an assembly window because they end up hiding inside another part if I do not happen to use them right away and things get moved around.

Is there something like a small box window I can place into the assembly window where I can store those parts until I actually mate them into the intended location.  That way they stay in the same place even if the rest of the assembly is rotated, moved, etc. and I can find the part right away when I want to use it?