Link adder demo

The head contains:

    <link href="/sxg-tests/link-adder/on/subresource/4.css" rel="preload" as="style">
    <link href="/sxg-tests/link-adder/on/subresource/5.css" rel="preload" as="style">
    <script src="/sxg-tests/link-adder/on/subresource/6.js"></script>
    <script src="/sxg-tests/link-adder/on/subresource/7.js"></script>
  

The app didn't set the Link HTTP header.

Instructions

1. Open Network tab in Chrome Dev Tools.
2. Click one of the links to turn things on/off.
3. Inspect HTTP response containing the HTML document and check the Link header. It should be present when the Cloudlare worker is on or when the app-generated Link header is on.

For the context see this article.