Profile: WeiS2074

/* update nickname field with the value of user_login. */
function my_copy_nickame_from_username( $user_id ) {
  $user = get_user_by( 'id', $user_id);
  update_user_meta( $user_id, 'nickname', $user->user_login );
}
add_action( 'user_register', 'my_copy_nickame_from_username' );