code: function updateItem(itemUi) {
      const option = itemUi._option
      if (option.disabled) {
        itemUi.setAttribute('disabled', '')
      } else {
        itemUi.removeAttribute('disabled')
      }
  
      if (option.tagName === 'OPTGROUP') {
        updateGroupUi(itemUi, option)
        itemUi.setAttribute('data-szn-options--optgroup-label', option.label)
        return
      }
  
      itemUi.innerText = option.text
      if (option.title) {
        itemUi.setAttribute('title', option.title)
      } else {
        itemUi.removeAttribute('title')
      }
  
      if (option.selected) {
        itemUi.setAttribute('data-szn-options--selected', '')
      } else {
        itemUi.removeAttribute('data-szn-options--selected')
      }
    }
docs: Updates the UI item to reflect the current state of its associated <code>option</code>/<code>optgroup</code>
  element.
  
  If the element represents an option group (<code>optgroup</code>), the children options will be updated as well.
  
  @param {HTMLElement} itemUi The element representing the UI of an <code>option</code>/<code>optgroup</code>
  element.