UR as 3-pane outliner

[schferk]

"Since the plus sign is possible in the parents pane where it's of no use, it should be realizable in the children pane where it would make UR a real 3-pane outliner!"

Sorry, its use in the parents pane is to be clickable, and thus allowing for navigating to siblings of the child item in question: smart! But then, just imagine, this same plus sign in the children pane, not just as an indicator "has / has no children"... but being clickable there, in order to expand that second tree: unbelievable! Please realize that, you're perfectly capable of it, or who would be if it weren't you? (And no, I'm not asking for moving items in the children pane, next, even if I tried and failed...)