https://learn.microsoft.com/en-us/dotnet/api/system.windows.contentelement.onisstyluscapturewithinchanged?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
ContentElement.OnIsStylusCaptureWithinChanged Method (System.Windows) | Microsoft Learn
Invoked when an unhandled IsStylusCaptureWithinChanged event is raised on this element. Implement this method to add class handling for this event.
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