As can be seen from the first round of testing in PR #15864, trying to update Puppeteer beyond version `19.0.0` completely breaks testing in Firefox. Curiously it does work locally when the `--noChrome` flag is being used, so it seems to be an issue with running tests in both Chrome *and* Firefox in parallel.

We need to fix this, likely by making some adjustments to our test-suite, such that we don't get "stuck" on an older version of Puppeteer without being able to update. (A temporary work-around could also be to disable testing in Chrome.)

(page + 1)
        );
        continue;
      }
      console.log(
        "TEST-UNEXPECTED-FAIL | forward-back-forward test " +
          task.id +
          " | in " +
          browser +
          " | first rendering of page " +
          (page + 1) +
          " != second"
      );
      numFBFFailures++;
    }
  }
  if (numFBFFailures > 0) {
    getSession(browser).numFBFFailures += numFBFFailures;
  } else {
    console.log(
      "TEST-PASS | forward-back-forward test " + task.id + " | in " + browser
    );
  }
}
function checkLoad(task, results, browser) {
  
  
  console.log("TEST-PASS | load test " + task.id + " | in " + browser);
}
function checkRefTestResults(browser, id, results) {