[about-blank-replacement.https.html]
  expected:
    if tsan: [ERROR, OK, FAIL]
    [OK, FAIL]
  [Popup initial about:blank is controlled, exposed to clients.matchAll(), and matches final Client.]
    expected: [PASS, FAIL]

  [Nested about:srcdoc is controlled and is exposed to clients.matchAll().]
    expected:
      if (os == "win") and debug and (processor == "x86_64"): [PASS, FAIL]
      if (os == "linux") and debug and fission: [PASS, FAIL]
      if os == "mac": [PASS, FAIL]