[element-mutation.html]
  [Declarative shadow DOM with shadowrootcustomelementregistry attribute without registry initialized should remain null registry after adoption.]
    expected: FAIL

  [An element with global registry should not change its registry when run append into a shadow tree with scoped registry.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run append out of the shadow tree.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run append into another shadow tree with different scoped registry.]
    expected: FAIL

  [An element with global registry should not change its registry when run appendChild into a shadow tree with scoped registry.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run appendChild out of the shadow tree.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run appendChild into another shadow tree with different scoped registry.]
    expected: FAIL

  [An element with global registry should not change its registry when run prepend into a shadow tree with scoped registry.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run prepend out of the shadow tree.]
    expected: FAIL

  [An element with scoped registry should not change its registry when run prepend into another shadow tree with different scoped registry.]
    expected: FAIL