diff --git a/source b/source index e6c462593cb..1c412b1d1e0 100644 --- a/source +++ b/source @@ -57156,11 +57156,26 @@ interface HTMLOptionElement : HTMLElement { null.

    +

  1. Let ancestorOptgroup be null.

    2. +

  2. For each ancestor of option's ancestors, in reverse tree order:

      +

    1. If ancestor is a datalist, hr, or + option element, then return null.

      2. + +
    2. +

      If ancestor is an optgroup element:

      + +
        +

      1. If ancestorOptgroup is not null, then return null.

        2. + +

      2. Set ancestorOptgroup to ancestor.

        3. +
      +
      3. +

    3. If ancestor is a select, then return ancestor.