[sibling-function-descriptors.tentative.html]
  [sibling-index() should not be allowed in @page properties]
    expected: FAIL

  [sibling-count() should not be allowed in @page properties]
    expected: FAIL

  [sibling-index() should not be allowed in @font-face descriptors]
    expected: FAIL

  [sibling-count() should not be allowed in @font-face descriptors]
    expected: FAIL

  [sibling-index() should not be allowed in @font-palette-values descriptors]
    expected: FAIL

  [sibling-count() should not be allowed in @font-palette-values descriptors]
    expected: FAIL

  [sibling-index() should not be allowed in @counter-style descriptors]
    expected: FAIL

  [sibling-count() should not be allowed in @counter-style descriptors]
    expected: FAIL

  [sibling-index() should not be allowed in @font-feature-values descriptors]
    expected: FAIL

  [sibling-count() should not be allowed in @font-feature-values descriptors]
    expected: FAIL