You can customize the header (also known as its title bar) with an alignable, descriptive text caption for your window, an optional icon or image, and whether the header should show or hide its minimize and maximize boxes. As with the rest of the dialog window, you have complete control over its styling and appearance with CSS. When the dialog appears minimized, only this header will be visible and you can control its displayed width through its MinimizedWidth property.

The dialog window's starting position is determined by its InitialPosition property. You can have it come up centered in the browser, or set the initial position manually through the Top and Left properties.

Users can reposition the window once it has been displayed. If you want to lock the window in place, you can set its Moveable property to False which will prevent the user from moving it.

WebDialogWindow™ can appear normal, minimized (usually with a narrower width and only the height necessary for the header to be shown), maximized to the browser window dimensions or hidden. It will remember its state, and buttons familiar to the user can appear on the header allowing the user to change the window's state interactively.