Thank you for writing.
The RibbonBar does not handle this sequence of adding a child form. I would like to suggest first to show the form and after that to do maximize:
|// Display the new form.
|newMDIChild.WindowState = FormWindowState.Maximized;
We are planning to handle this in future though. Don't hesitate to contact us if you have other questions.
the Telerik team
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