Win32Exception: Invalid window handle
--NativeErrorCode: 1400
StackTrace:
   at MS.Internal.PointUtil.ScreenToClient(Point pointScreen, PresentationSource presentationSource)
   at System.Windows.Controls.PopupControlService.ConvexHull.ContainsMousePoint()
   at System.Windows.Controls.PopupControlService.MouseHasLeftSafeArea()
   at System.Windows.Controls.PopupControlService.OnMouseMove(IInputElement directlyOver)
   at System.Windows.Controls.PopupControlService.OnPostProcessInput(Object sender, ProcessInputEventArgs e)
   at System.Windows.Input.InputManager.RaiseProcessInputEventHandlers(ProcessInputEventHandler postProcessInput, ProcessInputEventArgs processInputEventArgs)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   at System.Windows.Input.MouseDevice.Synchronize()
   at System.Windows.Input.MouseDevice.PostProcessInput(Object sender, ProcessInputEventArgs e)
   at System.Windows.Input.InputManager.RaiseProcessInputEventHandlers(ProcessInputEventHandler postProcessInput, ProcessInputEventArgs processInputEventArgs)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
   at System.Windows.Interop.HwndMouseInputProvider.System.Windows.Input.IMouseInputProvider.CaptureMouse()
   at System.Windows.Input.MouseDevice.Capture(IInputElement element, CaptureMode captureMode)
   at System.Windows.Controls.Primitives.MenuBase.set_IsMenuMode(Boolean value)
   at System.Windows.Controls.ContextMenu.OnPopupOpened(Object source, EventArgs e)
   at System.Windows.FrameworkElement.RaiseClrEvent(EventPrivateKey key, EventArgs args)
   at System.Windows.Controls.Primitives.Popup.CreateWindow(Boolean asyncCall)
   at System.Windows.Controls.Primitives.Popup.OnIsOpenChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
   at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   at System.Windows.DependencyObject.InvalidateProperty(DependencyProperty dp, Boolean preserveCurrentValue)
   at System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange)
   at System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange)
   at MS.Internal.Data.PropertyPathWorker.UpdateSourceValueState(Int32 k, ICollectionView collectionView, Object newValue, Boolean isASubPropertyChange)
   at MS.Internal.Data.PropertyPathWorker.OnDependencyPropertyChanged(DependencyObject d, DependencyProperty dp, Boolean isASubPropertyChange)
   at System.Windows.Data.BindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpression.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.DependentList.InvalidateDependents(DependencyObject source, DependencyPropertyChangedEventArgs sourceArgs)
   at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   at System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   at Quicker.Utilities.UI.DropDownButton.OpenMenu()
   at Quicker.Utilities.UI.DropDownButton.OnClick()
   at System.Windows.Input.AccessKeyManager.ProcessKey(List`1 targets, String key, Boolean existsElsewhere, Boolean userInitiated)
   at System.Windows.Input.AccessKeyManager.ProcessKey(Object scope, String key, Boolean isMultiple)
   at System.Windows.Interop.HwndSource.OnMnemonicCore(MSG& msg, ModifierKeys modifiers)
   at System.Windows.Interop.HwndSource.OnPreprocessMessage(Object param)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

Win32Exception: Invalid window handle
--NativeErrorCode: 1400
StackTrace:
   at MS.Win32.UnsafeNativeMethods.GetMessageW(MSG& msg, HandleRef hWnd, Int32 uMsgFilterMin, Int32 uMsgFilterMax)
   at System.Windows.Threading.Dispatcher.GetMessage(MSG& msg, IntPtr hwnd, Int32 minMessage, Int32 maxMessage)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at Quicker.App.Main()