When displaying the database explorer and the properties window simultaneously on the left pane of the form, the Properties pane overlaps the bottom of the database explorer pane, so that the down arrow of the scroll bar is not visible. Even if the properties pane is unpinned or closed, the Database explorer resizes so that the down arrow is STILL not visible, as the bottom of the scroll bar is now 'hiding' behind the status bar...
This has the effect that I can scroll UP one line at a time in the database explorer, but, I can't scroll down one line at a time. Which is irritating.

www.oquin.com/msc/oradevelop.jpg