Not possible to "let go" of frame divider on msdn site. This happens on both TOT and 2.0.3 Click on the frame divider to try and resize the frame. Notice that no matter what you do, you can't ever stop resizing the frame. TOT also seems to cause the side-frame (list of functions) to start with width 0.
This works for me with a local debug build of WebKit r30458. I think it may be closed.
Works for me, too.