Given a <tree rows="5"/> (as e.g. a place-holder for items to be added on a buton press) one would expect the tree to take up the room of 5 rows at that point, which currently it doesn't. Instead its height is collapsed to "0". Attaching a test-case.
Replace the "empty" tree with the commented out section in the testcase if you're not sure what I'm talking about.
Make sure this works with your new listbox, joe, and also we'll need to add support for this to outliner. This bug can cover all of those things.
Just tested my current listbox implementation, and fortunately this is already working correctly.
this works ok in listbox, and since tree is going the way of the dodo, I will not be fixing this in the tree code