Commerce Core uses our Address module to add address fields to various entities, including stores and customer profiles. Address fields are not added directly to orders, payment methods, or shipments – the things for which we might typically expect an address to be selected from an address book. Those entities instead reference profiles with addresses that represent billing and shipping addresses.
As a result, a user’s address book is basically just a collection of profiles with the same uid as the user. These profiles are created in various ways:
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