Multiple Window support is new in Silverlight 5: You can display multiple Window instances in trusted, out-of-browser applications. This enables you to create non-modal dialog boxes, tear-off windows, and user-adjustable layouts that can span multiple monitors. Silverlight’s built-in support for Modal Windows is limited to the MessageBox class. MessageBox Silverlight’s MessageBox.Show static method can open a modal dialog box, which is good for error messages, but it looks a bit basic and you can’[...]