text: function do_strikethrough(checkbox, id)
  {
      elem = document.getElementById(`li_${id}`)
      if (checkbox.checked == true) {
          elem.innerHTML = elem.innerText.strike()
      } else {
          elem.innerHTML = elem.innerText
      }
  
      console.debug(`Setting ${id} to ${checkbox.checked}`)
      localStorage.setItem(id, checkbox.checked)
  }
  
  function init()
  {
      for (let id = 0; ; id++) {
          elem = document.getElementById(`li_${id}`);
          if (elem == null) break;
          
          console.debug(`${id} is ${localStorage.getItem(id)}`);
          if (localStorage.getItem(id) == 'true') {
              elem.innerHTML = elem.innerText.strike();
              checkbox = document.getElementById(`checkbox_${id}`);
              checkbox.checked = true;
          } else {
              elem.innerHTML = elem.innerText
              // checkbox.value = false;
          }
      }
  }