code: function hasTextMimetype(types) {
        if (!types) return true;
        for (var i = 0; i < types.length; i++) {
          if (types[i] === 'Text' || types[i] === 'text/plain') return true;
        }
        return false;
      }
docs: Check if the dataTransfer object contains a drag type that we can handle. In old versions
  of IE the types collection will not even be there, so we just assume a drop is possible.