15. Sortable multi input

'multi_input' => array(
   'type' => 'multi_input',
   'label' => esc_html__( 'Multi Input', 'my-domain' ),
   'options' => array(
      array(
         'key' => 'facebook',
         'label' => esc_html__( 'Facebook', 'my-domain' ),
         'value' => '#facebook'
      ),
      array(
         'key' => 'twitter',
         'label' => esc_html__( 'Twitter', 'my-domain' ),
      ),
      array(
         'key' => 'instagram',
         'label' => esc_html__( 'Instagram', 'my-domain' ),
      ),
   )
),