I am wondering, when I have a theme for my magento page, and there's a Mega Menu include, it not happend, when I add a new category, it automatic add in the navigation.
Or do I something wrong? Is there a solution to do it?
I don't think you are doing something wrong. Not sure what MegaMenu you have in your theme, but usually it's not connected to the categories and you have to assign them manually - in this way you have a full control of what you show in the navigation specifically. Maybe it can be customized to be automatic, that depends on the MegaMenu extension. I suggest to contact the theme developers.
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