Intermittent ERROR (expected TIMEOUT) in /html/browsers/browsing-the-web/history-traversal/pageswap/pageswap-initial-navigation.html (WebDriver) #40387

Stable unexpected results (1): 
  ▶ ERROR [expected TIMEOUT] /html/browsers/browsing-the-web/history-traversal/pageswap/pageswap-initial-navigation.html
  │   → uncaught exception: Error: assert_true: pageswap fired expected true got false
  │ 
  └ runTest/frameWindow.onpagehide@http://web-platform.test:8000/html/browsers/browsing-the-web/history-traversal/pageswap/pageswap-initial-navigation.html:21:18