firefox/testing/web-platform/meta/css/css-rhythm/parsing/block-step-insert-valid.html.ini

[block-step-insert-valid.html]
  [e.style['block-step-insert'\] = "content-box" should set the property value]
    expected: FAIL

  [e.style['block-step-insert'\] = "margin-box" should set the property value]
    expected: FAIL

  [e.style['block-step-insert'\] = "padding-box" should set the property value]
    expected: FAIL