不正确的jquery-chosen-sortable排序顺序

Question

使用jquery-chosen-sortable https://github.com/mrhenry/jquery-chosen-sortable 但如果提交两次，则正确的顺序。

<form method="post" id="f1">
  <div id="container">

    <h2>Selected and Disabled Support</h2>
    <div class="side-by-side clearfix">
      <p>Chosen automatically highlights selected options and removes disabled options.</p>
      <div>
        <em>Multiple Select</em>
        <select data-placeholder="Your Favorite Types of Bear" style="width:350px;" multiple class="chosen chzn-sortable" id="test_me" name="nl_item[attributes][link][]" tabindex="8">
          <option value=""></option>
          <option>American Black Bear</option>
          <option>Asiatic Black Bear</option>
          <option>Brown Bear</option>
          <option>Giant Panda</option>
          <option selected>Polar Bear</option>
          <option selected>Sloth Bear</option>
          <option disabled>Sun Bear</option>
          <option disabled>Spectacled Bear</option>
        </select>
      </div>
      <button type="submit">submit</button>
    </div>

  </div>
  </form>
 <script>
  $( "form#f1" ).on( "submit", function () {
    var str = $( "form#f1" ).serialize();
    console.log( str );// <---
    return false;
  } );
 </script>