Please describe the problem:
There are many applications I use which have list components with changing
contents.  If the contents of the list changes and the new list has less items
than the previous list and the scroll position was at (or near) the bottom of
the box, the new box will look emply (or have a big white space at the bottom)
even though there are items in the list.  You have to scroll up manually to see
them.

Additionally, if you are deleting single items from the list (as in Gaim 1.5
when deleting old away messages), the scroll bar will get smaller even though
the list is getting shorter and eventually you can be looking at a white list of
nothing with all the remaining away messages hidden above view.

The problem seems to be in how the list handles deletions.  If you are at the
bottom of a list and the length decreases the scroll position should be updated
to reflect the change. i.e. the bottom of the list should be redefined to the
new last item.  If the list changes entirely I would expect the scroll to go to
the top of the list.

This behavior is present in a number of applications and has succeeded in
confusing a user I was trying to switch to Gnome last week.

Steps to reproduce:


Actual results:


Expected results:


Does this happen every time?


Other information: