docs: function() {
        var that   = this,
            iframe = doc.createElement("iframe");
        iframe.className = "wysihtml5-sandbox";
        wysihtml5.dom.setAttributes({
          "security":           "restricted",
          "allowtransparency":  "true",
          "frameborder":        0,
          "width":              0,
          "height":             0,
          "marginwidth":        0,
          "marginheight":       0
        }).on(iframe);
  
        // Setting the src like this prevents ssl warnings in IE6
        if (wysihtml5.browser.throwsMixedContentWarningWhenIframeSrcIsEmpty()) {
          iframe.src = "javascript:'<html></html>'";
        }
  
        iframe.onload = function() {
          iframe.onreadystatechange = iframe.onload = null;
          that._onLoadIframe(iframe);
        };
  
        iframe.onreadystatechange = function() {
          if (/loaded|complete/.test(iframe.readyState)) {
            iframe.onreadystatechange = iframe.onload = null;
            that._onLoadIframe(iframe);
          }
        };
  
        return iframe;
      }