The content area of RadEditor is editable IFRAME, which uses the underlining Rich Text Editing engine of the browser
where it operates. The observed behavior is browser behavior and it is the browser that rearranges the attributes in the HTML tags. You can reproduce the same behavior in the attached HTML page having an editable IFRAME elements in it as well as in our competitors' editors.
Here is a video demonstration: http://screencast.com/t/wZHr4wK9
the Telerik team
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