msw/test/browser/msw-api/setup-worker/scenarios/iframe-isolated-response/one.html

<script>
  window.request = () => {
    const { worker, http } = window.parent.msw

    function isolatedResolver(resolver) {
      return (info) => {
        if (info.request.referrer !== location.href) {
          return
        }
        return resolver(info)
      }
    }

    worker.use(
      http.get(
        './resource',
        isolatedResolver(({ request }) => {
          return new Response('one')
        }),
      ),
    )

    return fetch('./resource')
      .then((response) => response.text())
      .then((data) => {
        const node = document.createElement('p')
        node.innerText = data
        document.body.appendChild(node)
      })
      .catch((error) => console.error(error))
  }

  document.addEventListener('click', window.request)
</script>