When using Implicit Styles setting the DropDownDisplayMode of a PaneGroup to Visible in the Office themes causes the DropDownButton to be invisible.
If there are more than 2 Panes in an PaneGroup closing one of the Panes with index bigger than 1 calls ActivePaneChanged event twice.
Removing item from the PanesSource collection causes NullReferenceException
When Saving and Loading a layout which has empty DocumentHost an ArgumentOutOfRangeException is thrown
Open a Window from a button placed inside the unpinned pane. The pane does not hide and the window is shown below it.