ndow.ShadyCSS.nativeShadow);
            assert.equal(origCssBuild, window.ShadyCSS.cssBuild);
            done();
          };
          document.head.appendChild(script);
        };
        document.head.appendChild(script);
      };
      document.head.appendChild(script);
    });
    test('Native CSS Custom Properties disabled if ShadyDOM is in use', () => {
      if (!window.ShadyDOM || !window.ShadyDOM.inUse) {
        assert.isTrue(
          window.ShadyCSS.nativeCss,
          'nativeCss should be 