I have a lot of documents opened right now, about 20.  When I open the Documents window (shift-F4), the window is too small, so it shows a scrollbar.  So I 
resize the window so I can see all 20 docs.  I double-click a doc, which selects that doc's tab in the editor, and automatically closes the Documents window.  
Sweet (so far, so good).

If I open the Documents window again, it has reverted to its default size and position.  Ideally, the window would remember its previous size and position, 
which would save me some time/effort.