This is a testharness.js-based test.
Found 24 FAIL, 0 TIMEOUT, 0 NOTRUN.
[FAIL] Null registry element with element parent without custom element registry attribute (scoped registry) appended to new document
  assert_equals: expected null but got object "[object CustomElementRegistry]"
[FAIL] Null registry element with declarative shadow root parent without custom element registry attribute appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with declarative shadow root parent with custom element registry attribute (global registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with imperative shadow root parent (null registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with imperative shadow root parent (global registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Global registry element with declarative shadow root parent without custom element registry attribute appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (null registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (global registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (scoped registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (null registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (global registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (scoped registry) appended to new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Null registry element with element parent without custom element registry attribute (scoped registry) adopted by new document
  assert_equals: expected null but got object "[object CustomElementRegistry]"
[FAIL] Null registry element with declarative shadow root parent without custom element registry attribute adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with declarative shadow root parent with custom element registry attribute (global registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with imperative shadow root parent (null registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Null registry element with imperative shadow root parent (global registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got null
[FAIL] Global registry element with declarative shadow root parent without custom element registry attribute adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (null registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (global registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with declarative shadow root parent with custom element registry attribute (scoped registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (null registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (global registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
[FAIL] Global registry element with imperative shadow root parent (scoped registry) adopted by new document
  assert_equals: expected object "[object CustomElementRegistry]" but got object "[object CustomElementRegistry]"
Harness: the test ran to completion.