A possible way to do this is to use the Copied event of the GridView. It occurs after the selected cells of the GridViewDataControl were copied to the Clipboard. That helps us get the already copied data in the clipboard with Clipboard.GetData() method and then replace it with the Clipboard.SetData() method. In order to display your content in one cell, you will need to remove the new line ("\n") of the initially copied clipboard data and then set it in the clipboard.
sender, Telerik.Windows.RadRoutedEventArgs e)
originalText = Clipboard.GetData(DataFormats.UnicodeText).ToString();
var updatedText = originalText.Replace(
I hope this helps.
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