    </paper-submenu>
          </paper-menu>
        </paper-submenu>

        <paper-submenu label="paper-submenu">
          <paper-item class="menu-trigger">paper-submenu</paper-item>
          <paper-menu class="menu-content sublist">
            <paper-submenu label="Properties">
              <paper-item class="menu-trigger">Properties</paper-item>
              <paper-menu class="menu-content sublist2">
                <paper-item>opened</paper-item>
              </paper-menu>
              </paper-