1. Resource Hints: dns-prefetch

    Gives a hint to the browser to perform a DNS lookup in the background to improve performance. This is indicated using `<link rel="dns-prefetch" href="https://example.com/">`

  2. Resource Hints: modulepreload

    Using `<link rel="modulepreload">`, browsers can be informed to prefetch module scripts without having to execute them, allowing fine-grained control over when and how module resources are loaded.

  3. Resource Hints: preconnect

    Gives a hint to the browser to begin the connection handshake (DNS, TCP, TLS) in the background to improve performance. This is indicated using `<link rel="preconnect" href="https://example-domain.com/">`

  4. Resource Hints: prefetch

    Informs the browsers that a given resource should be prefetched so it can be loaded more quickly. This is indicated using `<link rel="prefetch" href="(url)">`

  5. Resource Hints: preload

    Using `<link rel="preload">`, browsers can be informed to prefetch resources without having to execute them, allowing fine-grained control over when and how resources are loaded. Only the following `as` values are supported: fetch, image, font, script, style, track.

  6. Resource Hints: prerender

    Gives a hint to the browser to render the specified page in the background, speeding up page load if the user navigates to it. This is indicated using `<link rel="prerender" href="(url)">`

  7. rel=noopener

    Ensure new browsing contexts are opened without a useful `window.opener`

  8. Link type "noreferrer"

    Links with `rel="noreferrer"` set do not send the request's "referrer" header. This prevents the destination site from seeing what URL the user came from.

  9. html element: area: `target="_blank"` implies `rel="noopener"` behavior

  10. html element: a: `target="_blank"` implies `rel="noopener"` behavior

  11. html element: link: rel: rel=expect

  12. html element: link: rel: rel=icon

  13. html element: link: rel: rel=manifest

  14. html element: link: rel: rel=modulepreload

  15. html element: link: rel: rel=preload: `as=fetch`

  16. html element: link: rel: rel=preload: `as=font`

  17. html element: link: rel: rel=preload: `as=image`

  18. html element: link: rel: rel=preload: `as=script`

  19. html element: link: rel: rel=preload: `as=style`

  20. html element: link: rel: rel=preload: `as=track`

  21. html element: link: rel: rel=prerender

  22. headers http header: sec-purpose: `sec-purpose` for `<link rel="prefetch">` prefetch

  23. http status code: 103: `rel=preconnect`

  24. http status code: 103: `rel=preload`