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To add a page to the menu you should click on the down arrow next to the page names in the right-hand column.
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Then you will see a list of pages. Click on click the desired page.
Click the Add button (the plus sign) to add the selected page to the menu.
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To delete a page from the menu you need to select it from the list on the left.
Click on click the Close button (the X) on the right of the page name.
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