dFolders { get; set; }          /// <summary>         ///     <para type="description">The &quot;singleValueExtendedProperties&quot; property, of type &quot;microsoft.graph.singleValueLegacyExtendedProperty&quot;.</para>         ///     <para type="description">This property is on the &quot;microsoft.graph.mailFolder&quot; type.</para>         /// </summary>         [ODataType("microsoft.graph.