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You can view and edit information about a file or folder in the information pane, such as required properties, recent activity or whom a file is shared with. To show or hide the information pane, select a file or folder and click 
on the right-hand side of the main menu. You can also view the information pane by right clicking a file or folder and selecting Details. 
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When you select a folder or file, the menu at the top left of the document library changes to a list of actions you can perform on that folder or file.
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