https://learn.microsoft.com/en-us/dotnet/api/system.windows.frameworkelement.oncontextmenuclosing?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0&redirectedfrom=MSDN
FrameworkElement.OnContextMenuClosing(ContextMenuEventArgs) Method (System.Windows) | Microsoft...
Invoked whenever an unhandled ContextMenuClosing routed event reaches this class in its route. Implement this method to add class handling for this event.
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