val rule = findMatchingRule(domainLabels)
    if (domainLabels.size == rule.size && rule[0][0] != EXCEPTION_MARKER) {
      return null // The domain is a public suffix.
    }

    val firstLabelOffset =
      if (rule[0][0] == EXCEPTION_MARKER) {
        // Exception rules hold the effective TLD plus one.
        domainLabels.size - rule.size
      } else {