The "Add Content Item" allows you to display an existing content item on your site in a widget area. Start typing the title of the content item in the "Piece of Content" box, and select the item from the list provided. Under "Content Settings," select how you would like the content item to be displayed ("Full Content," "Teaser," etc.).
NOTE: Currently, when adding a new Content Item widget, the Preview window will default to an existing content item. You can choose another item following the instructions above.
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