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Empty categories and subcategories are marked with the “!” sign on the folder.
Displaying empty categories without subcategories
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Click on the dashed blue underlined text “Display” next to the dashed blue underlined text “Empty (no subcategories)”.
Click on the desired menu item (for example, Display).
Once the current page has been automatically refreshed, after clicking, the category will be displayed both on the website and in the admin area.