The RadEditor control is designed to be an XHTML editor and due to that when a full page editing is in actions (means taht a full page HTML is inserted) then the editor actually shows its HEAD element.
Before that one is existing but just hidden from the HTML mode. Ones the user insert full HTML, it is appropriately shown and can by edited.
Note that the HEAD element cannot be removed as this is a strict HTML page and one is required to be in the HTML markup and this is not a restriction from the Editor but a general HTML-editing matter.
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