If the ID, query string or hash fields are enabled, they are made available on every nav menu item. The custom fields are implemented to work with the Screen Options like the other nav menu item fields. Below are additional details about the custom fields.
The ID applied to the list item. If default IDs are enabled, the value in this field will replace the default.
The ID applied to the link tag.
The CSS class(es) applied to the link tag.
Query string values added to the URL. If the URL already contains a query string, it will be appended to the value in this field.
Hash appended to the end of the URL. If a hash already exists in the URL, it will be replaced with the value in this field.
Last updated on November 17, 2020