function headerValueEquals (lhs, rhs) {
  if (lhs == null && rhs == null) {
    return true
  }

  if ((lhs == null && rhs != null) ||
      (lhs != null && rhs == null)) {
    return false
  }

  if (Array.isArray(lhs) && Array.isArray(rhs)) {
    if (lhs.length !== rhs.length) {
      return false
    }

    return lhs.every((x, i) => x === rhs[i])
  }

  return lhs === rhs
}
@param {string|string[]|null|undefined} lhs
@param {string|string[]|null|undefined} rhs
@returns {boolean}