Thanks for your interest in RadControls for WinForms and particularly in RadRibbonBar.
The RadRibbonBar does not support this behavior yet, but we are working on it and it will be on the feature list of one of our next releases. Much of the MS RibbonBar functionality is implemented though and we will be happy if you provide us with your feedback on the RadRibbonBar and on the other RadControls for WinForms as well.
Do not hesitate to write back if you have any other questions or new suggestions.
the Telerik team
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