Editing Menu Structure
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Use Add New Item, Remove Item, Move Item... buttons under the menu structure treeview to add new items, to remove items, and to arrange items into the menu hierarchy.
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You can enter information for each individual item, such as text and link, as you populate the menu, or you can do this later.
Creating a submenu
To create a submenu click Add New Item and then move the new item to the right by clicking Move Item Right
.
Import menu structure
To import a menu structure select "Import Menu Structure ..." in the File menu. See Import Menu Structure.