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The Navigation Pane contains several sub-panes. If a specific pane isn’t visible, you can display it by right clicking on the View tab. Next click Show/Hide in the expansion menu. Finally, click Navigation Panes and choose an optionNavigation Pane. An expansion menu will appear with several items to choose from. A checkmark indicates that that pane is visible in the Navigation Pane. When you click on a new sub-pane, it will appear in the Navigation Pane. The 3 most important panes (relevant to accessibility) in the Navigation Pane are Content, Order, and Tags.
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