The features are the same, but you are matching your catalogue categories with the channel categories. This enables the channel to classify your products in the search filters and the website tree view.
On this new platform "Category Matching" is the second stage that you should complete when configuring a new channel.
You will of course be able to return to this stage once your products are online in order to update the matching for any new categories that you add to your catalogue at a later date.
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