This is a testharness.js-based test.
Found 12 FAIL, 0 TIMEOUT, 0 NOTRUN.
[FAIL] shadowed pagereveal (document.body)
  assert_equals: alternative body should reflect expected (function) function "() => 0" but got (undefined) undefined
[FAIL] shadowed pageswap (document.body)
  assert_equals: alternative body should reflect expected (function) function "() => 0" but got (undefined) undefined
[FAIL] shadowed unload (document.body)
  assert_equals: alternative body should reflect expected (function) function "() => 0" but got (object) null
[FAIL] not shadowed copy (document.body)
  assert_equals: window should reflect expected (object) null but got (undefined) undefined
[FAIL] not shadowed cut (document.body)
  assert_equals: window should reflect expected (object) null but got (undefined) undefined
[FAIL] not shadowed paste (document.body)
  assert_equals: window should reflect expected (object) null but got (undefined) undefined
[FAIL] shadowed pagereveal removal (document.body)
  assert_equals: body should reflect changes to itself expected (object) null but got (undefined) undefined
[FAIL] shadowed pageswap removal (document.body)
  assert_equals: body should reflect changes to itself expected (object) null but got (undefined) undefined
[FAIL] shadowed pagereveal on body fires when event dispatched on window
  assert_true: expected true got undefined
[FAIL] shadowed pageswap on body fires when event dispatched on window
  assert_true: expected true got undefined
[FAIL] shadowed rejectionhandled on body fires when event dispatched on window
  assert_true: expected true got undefined
[FAIL] shadowed unload on body fires when event dispatched on window
  assert_true: expected true got undefined
Harness: the test ran to completion.