Changing the Shape of Toolbars

If a toolbar does not fill the whole window (from left to right or vertically, depending on its orientation) the toolbar dock is visible as the extra blank space at either side of the toolbar, separated from the toolbar by the toolbar border. 

Excel Tip. A toolbar that contains a drop-down list box, such as the Style box, cannot be placed in a vertical position in the left or right toolbar docks. 

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