docs: function getDataTransferItems(dataTransfer) {
          var items = {};
  
          if (dataTransfer) {
            // Use old WebKit/IE API
            if (dataTransfer.getData) {
              var legacyText = dataTransfer.getData('Text');
              if (legacyText && legacyText.length > 0) {
                if (legacyText.indexOf(mceInternalUrlPrefix) == -1) {
                  items['text/plain'] = legacyText;
                }
              }
            }
  
            if (dataTransfer.types) {
              for (var i = 0; i < dataTransfer.types.length; i++) {
                var contentType = dataTransfer.types[i];
                try { // IE11 throws exception when contentType is Files (type is present but data cannot be retrieved via getData())
                  items[contentType] = dataTransfer.getData(contentType);
                } catch (ex) {
                  items[contentType] = ""; // useless in general, but for consistency across browsers
                }
              }
            }
          }
  
          return items;
        }