[pseudo-classes-after-part.html]
  ["::part(mypart):future" should be a valid selector]
    expected: FAIL

  ["::part(mypart):past" should be a valid selector]
    expected: FAIL

  ["::part(mypart):paused" should be a valid selector]
    expected: FAIL

  ["::part(mypart):picture-in-picture" should be a valid selector]
    expected: FAIL

  ["::part(mypart):playing" should be a valid selector]
    expected: FAIL

  ["::part(mypart):xr-overlay" should be a valid selector]
    expected: FAIL