// Clear Alt-Svc caching first.
      let responseText = &quot;&quot;;
      await fetch(&quot;https://altsvc.arthuredelstein.net:4433/clear&quot;);
      await sleepMs(100);
      responseText = await fetchText(&quot;https://altsvc.arthuredelstein.net:4433/protocol&quot;);
      console.log(&quot;after clear:&quot;, responseText);
      // Store &quot;h3&quot; state in Alt-Svc cache
      await fetch(&quot;https://altsvc.arthuredelstein.net:4433/set&quot;);
      await sleepMs(100);
      responseText = aw