code: function updateUi(instance) {
      if (!instance._options) {
        return
      }
  
      if (instance._options.disabled) {
        instance._root.setAttribute('disabled', '')
      } else {
        instance._root.removeAttribute('disabled')
      }
      if (instance._options.multiple) {
        instance._root.setAttribute('data-szn-options--multiple', '')
      } else {
        instance._root.removeAttribute('data-szn-options--multiple')
      }
  
      updateGroupUi(instance._root, instance._options)
      if (instance._mounted) {
        const options = instance._options.options
        let lastSelectedIndex = -1
        for (let i = options.length - 1; i >= 0; i--) {
          if (options.item(i).selected) {
            lastSelectedIndex = i
            break
          }
        }
        scrollToSelection(instance, instance._options.selectedIndex, lastSelectedIndex)
      }
    }
docs: Updates the UI, if the provided szn-options element has already been provided with the options to display. The
  functions synchronizes the displayed UI to reflect the available options, their status, and scrolls to the last
  selected option if it is not visible.
  
  @param {SznElements.SznOptions} instance The szn-options element's instance.