[Slotable-interface.html]
  type: testharness
  prefs: [dom.webcomponents.enabled:true]
  [assignedSlot must return null when the node does not have an assigned node]
    expected: FAIL

  [assignedSlot must return the assigned slot]
    expected: FAIL

  [assignedSlot must return null when the assigned slot element is inside a closed shadow tree]
    expected: FAIL