[idlharness.window.html]
  [ElementInternals interface: attribute states]
    expected: FAIL

  [CustomStateSet interface: existence and properties of interface object]
    expected: FAIL

  [CustomStateSet interface object length]
    expected: FAIL

  [CustomStateSet interface: existence and properties of interface prototype object's "constructor" property]
    expected: FAIL

  [Stringification of customStateSet]
    expected: FAIL

  [CustomStateSet must be primary interface of customStateSet]
    expected: FAIL

  [CustomStateSet interface object name]
    expected: FAIL

  [CustomStateSet interface: customStateSet must inherit property "add(DOMString)" with the proper type]
    expected: FAIL

  [CustomStateSet interface: operation add(DOMString)]
    expected: FAIL

  [CustomStateSet interface: existence and properties of interface prototype object]
    expected: FAIL

  [CustomStateSet interface: calling add(DOMString) on customStateSet with too few arguments must throw TypeError]
    expected: FAIL

  [CustomStateSet interface: existence and properties of interface prototype object's @@unscopables property]
    expected: FAIL

  [CustomStateSet interface: setlike<DOMString>]
    expected: FAIL