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This property is crucial for panel controls because you must adjust the panel widths before your columns will line up side by side. For tab controls, you access the width property by clicking the unlabeled area to the right of the last tab in your tab group; the width you specify will be applied uniformly to each tab in group. (See Panels and Tabs for more details.)
There is no Width property for section or repeat controls; however, you can edit the Width property of controls you drag inside these controls. Also, if you drag a section or repeat inside other group controls, Live Forms automatically adjusts the width to a sensible size.
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