Customizing the Application > Customizing the Ribbon > To Minimize or Maximize the Ribbon
  
To Minimize or Maximize the Ribbon
Toggle the ribbon by doing one of the following operations:
Double-click the name of an active tab.
Right-click the ribbon or the Quick Access Toolbar and select or clear the Minimize the Ribbon check box in the shortcut menu.
Press CTRL+F1.
The ribbon is minimized or maximized.
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To use the ribbon while it is minimized, click a tab name. The ribbon is maximized and the tab is selected. After you click a button, the ribbon is automatically minimized.