System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Linq.Enumerable.ArrayWhereIterator`1.ToArray(ReadOnlySpan`1 source, Func`2 predicate)
   at System.Linq.Enumerable.ListWhereIterator`1.ToArray()
   at TomsToolbox.Essentials.WeakEventSource`1.Raise(Object sender, TEventArgs e)
   at ICSharpCode.ILSpy.ContextMenuProvider.<>c__DisplayClass23_0.<ShowContextMenu>g__ContextMenu_Closing|0(Object sender, EventArgs e)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.Controls.Primitives.Popup.OnClosed(EventArgs e)
   at System.Windows.Controls.Primitives.Popup.DestroyWindow()
   at System.Windows.Threading.DispatcherTimer.FireTick()
   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)