This is a testharness.js-based test.
Found 17 FAIL, 0 TIMEOUT, 0 NOTRUN.
[FAIL] Append h1 to #ancestor: #has_heading_1
  assert_equals: expected "rgb(255, 0, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h1 to #ancestor: #has_heading_1_2
  assert_equals: expected "rgb(0, 128, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h2 to #ancestor: #has_heading_1
  assert_equals: expected "rgb(255, 0, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h2 to #ancestor: #has_heading_2
  assert_equals: expected "rgb(255, 165, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h2 to #ancestor: #has_heading_1_2
  assert_equals: expected "rgb(0, 128, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h3 to #ancestor: #has_heading_1
  assert_equals: expected "rgb(255, 0, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h3 to #ancestor: #has_heading_2
  assert_equals: expected "rgb(255, 165, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h3 to #ancestor: #has_heading_3
  assert_equals: expected "rgb(255, 255, 0)" but got "rgb(128, 128, 128)"
[FAIL] Append h3 to #ancestor: #has_heading_1_2
  assert_equals: expected "rgb(0, 128, 0)" but got "rgb(128, 128, 128)"
[FAIL] Remove h1 from #ancestor: #has_heading_2
  assert_equals: expected "rgb(255, 165, 0)" but got "rgb(128, 128, 128)"
[FAIL] Remove h1 from #ancestor: #has_heading_3
  assert_equals: expected "rgb(255, 255, 0)" but got "rgb(128, 128, 128)"
[FAIL] Remove h1 from #ancestor: #has_heading_1_2
  assert_equals: expected "rgb(0, 128, 0)" but got "rgb(128, 128, 128)"
[FAIL] Remove h2 from #ancestor: #has_heading_3
  assert_equals: expected "rgb(255, 255, 0)" but got "rgb(128, 128, 128)"
[FAIL] Insert h1 adjacent to #sibling: #has_adjacent_heading_1
  assert_equals: expected "rgb(0, 0, 255)" but got "rgb(128, 128, 128)"
[FAIL] Insert h1 adjacent to #sibling: #adjacent_heading_1
  assert_equals: expected "rgb(128, 0, 128)" but got "rgb(128, 128, 128)"
[FAIL] Replace div with h1 in #ancestor: #has_heading_1
  assert_equals: expected "rgb(255, 0, 0)" but got "rgb(128, 128, 128)"
[FAIL] Replace div with h1 in #ancestor: #has_heading_1_2
  assert_equals: expected "rgb(0, 128, 0)" but got "rgb(128, 128, 128)"
Harness: the test ran to completion.