WPF and how to move between graphics and XAML

When designing windows/controls in a WPF form there are two panes. One (upper) with the graphics and one (lower) with the XAML code. How do one navigate between these two through the keyboard? The answer is shift-F7.

F7 moves from designer to code.

Shift-F7 is the reverse and moves from code to designer and in the designer toggles between the graphics pane and the XAML pane.

Update: Now I can only switch from XAML to code behind but not back and not between the xaml/designer panes.  New machine, new OS, new service pack, new addons.  I don't know what to blame.