             left += 60;
          }
          top += 30;
      }
      document.body.appendChild(container);
  }

  function startTest() {
    populateData();

    PerfTestRunner.forceLayout();

    PerfTestRunner.measureTime({
      description: "Measures performance of changing text nodes content.",
      run: function() {
        for (let i = 0; i < textNodes.length; i++) {
          textNodes[i].data = '' + (100 * Math.random()).toFixed(2);
        }

        PerfTestRunner.forceLayout();
      },
    