Popups
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Shows how you can use the Popup control to show dialogs and popups.

The Popup control is a container that provides automatic positioning, focus, 
and keyboard handling making it easy to show dialogs or popups associated
with other elements on the page.

This sample shows how you can use the Popup control to show several dialogs
(with validation, focus, and keyboard handling) and how you can attach
popups that show additional information about any element on the page.