After installing this update, WPF apps may crash with a callstack similar to
Exception Info: System.NullReferenceException at System.Windows.Interop.HwndMouseInputProvider.HasCustomChrome(System.Windows.Interop.HwndSource, RECT ByRef)
at System.Windows.Interop.HwndMouseInputProvider.GetEffectiveClientRect(IntPtr)
at System.Windows.Interop.HwndMouseInputProvider.PossiblyDeactivate(IntPtr, Boolean)
at System.Windows.Interop.HwndMouseInputProvider.Dispose()
This occurs when disposing an HwndSource whose RootVisual is null, a situation that arises in Visual Studio when docking or splitting windows, and could arise in other apps.