The OnClientPasteHtml event works only for design mode, because all editor's tools are designed to work in Design mode only. The content area of RadEditor in HTML mode is a standard textarea and the built-in tools of the editor are designed to work in the editable iframe area in design mode.
If you would like you can get a reference to this textarea in HTML mode via the editor.get_textArea()
method and implement your own paste handling mechanism using the browser's API.
All the best,
the Telerik team
Registration for Q1 2011 What’s New Webinar Week is now open. Mark your calendar for the week starting March 21st and book your seat
for a walk through all the exciting stuff we ship with the new release!