title: Dropzone.js - Error: Invalid `clickable` option provided
body: <p>I'm using dropbox.js and I get this error: <strong>Error: Invalid <code>clickable</code> option provided</strong>. I've tried all solutions possible about the <code>clickable</code> option. </p>
  
  <ol>
  <li><code>clickable: "#add-new",</code></li>
  <li><code>clickable: '#add-new',</code></li>
  <li><code>clickable: ['#add-new'],</code></li>
  <li><code>clickable: ["#add-new"],</code></li>
  </ol>
  
  <p>I've updated my version but still I don't know how to fix it. My objective is to append a button on each added element (previewTemplate) for adding new elements further.</p>
  
  <p>Is there any workaround to fix this or another solution?
  Thanks.</p>
  
  <pre><code>var myDropzone = new Dropzone('div#myDropzoneElement2', {
          maxThumbnailFilesize: 2,
          maxFilesize: 2,
          acceptedFiles:'image/*',
          clickable: ["#add-new"],
          thumbnailWidth: 250,
          thumbnailHeight: 125,
          url: dropzoneUrl,
          previewTemplate: "&lt;div class=\"dz-preview dz-file-preview col-sm-12\"&gt;\n  &lt;div class=\"row\"&gt;&lt;div class=\"col-sm-5 col-md-4\"&gt;&lt;div class=\"dz-image\"&gt;&lt;img data-dz-thumbnail width=\"100%\"/&gt;&lt;/div&gt;&lt;div class=\"dz-filename\"&gt;(&lt;span data-dz-size&gt;&lt;/span&gt;)&lt;/div&gt;&lt;/div&gt;\n  &lt;div class=\"col-sm-7 col-md-8\"&gt;&lt;div class=\"row\"&gt;&lt;div class=\"col-sm-12\"&gt;&lt;input type=\"text\" id=\"itemtitle\" placeholder=\"Project title\"name=\"itemtitle\" class=\"info-title form-control\"&gt;&lt;/div&gt;\n &lt;div class=\"top-15 col-sm-12 \"&gt;&lt;textarea id=\"itemdescription\" placeholder=\"Describe here the project with essential informations like material and methods applied. Remember the 5Ws and how!\" rows=\"5\" name=\"itemdescription\" class=\"form-control info-description\"&gt;&lt;/textarea&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;\n   &lt;div class=\"dz-error-message\"&gt;&lt;span data-dz-errormessage&gt;&lt;/span&gt;&lt;/div&gt;\n  &lt;div class=\"dz-success-mark\"&gt;\n    &lt;/div&gt;\n     &lt;div class=\"row\"&gt;&lt;div class=\"col-sm-12\"&gt;&lt;div class=\"dz-progress\"&gt;&lt;span class=\"dz-upload\" data-dz-uploadprogress&gt;&lt;/span&gt;&lt;/div&gt;&lt;/div&gt;&lt;div class=\"col-sm-6\"&gt;&lt;a class=\"dz-remove\" href=\"javascript:undefined;\" data-dz-remove&gt;Remove&lt;/a&gt;&lt;/div&gt;&lt;div class=\"col-sm-6\"&gt;&lt;button type=\"button\" class=\"dz-update\" id=\"updateinformations\" href=\"javascript:undefined;\" disabled&gt;Update&lt;/button&gt;&lt;/div&gt;&lt;div class=\"col-sm-6\"&gt;&lt;button type=\"button\" id=\"add-new\"&gt;Add New&lt;/button&gt;&lt;/div&gt;&lt;/div&gt;\n   &lt;/div&gt;",
      });
  </code></pre>