https://learn.microsoft.com/en-us/dotnet/api/system.windows.contentelement.previewgivefeedback?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
ContentElement.PreviewGiveFeedback Event (System.Windows) | Microsoft Learn
Occurs when a drag-and-drop operation is started.
event systemwindowsmicrosoftlearn