WooCommerce, by default, will change the WordPress display name for any given user to their First Name Last Name when that user makes a purchase through WooCommerce. This probably makes a lot of sense in the interest of customer relationships, but there may be cases where this is undesirable, say in the case of a forum on your site that uses the display name. Perhaps users would rather maintain a bit of anonymity on your forums. Not to worry, however, WooCommerce provides a filter that can be used to prevent this behavior. The filter is named woocommerce_update_customer_args and here is a quick example of how that can be implemented to set the display name to the username:
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