[observe.html]
  prefs: [layout.css.zoom.enabled:false]
  expected:
    if (os == "mac") and not debug: [OK, TIMEOUT]
  [guard]
    expected:
      if (os == "mac") and not debug: [PASS, NOTRUN]

  [test6: iframe notifications]
    expected:
      if (os == "mac") and not debug: [PASS, FAIL]

  [test8: simple content-box observation]
    expected:
      if (os == "mac") and not debug: [PASS, FAIL]

  [test0: simple observation]
    expected:
      if (os == "mac") and not debug: [PASS, FAIL]