Add semantic page landmarks.

Identify the header, navigation, main content and footer with semantic HTML.

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Example</title>
</head>
<body>
<header>Example</header><nav aria-label="Main"><a href="#content">Content</a></nav><main id="content"><h1>Welcome</h1></main><footer>End</footer>
</body>
</html>

Expected output EXAMPLE

1 match is present for the “Main” navigation.
1 match is present for the main.

Details

Save as example.html and open in a modern browser. Expected output describes the tested DOM behavior; the assertions below exercise the example in Chromium.

✓ Verified

Tested on Ubuntu 24.04.5 LTS · 2026-11-02 18:00:55 UTC · Chromium 141.0.7390.37 · libc6 2.39-0ubuntu8.9; Playwright 1.56.0

Test inputs, results and environment

The exact published code ran in a dedicated Linux test container with prepared inputs. Unprivileged snippet process, external networking disabled, read-only root filesystem, and a fresh temporary working directory. Fixtures and output records are isolated from the application database. Testing covers this example and its stated checks, not every input, operating system, or runtime version. The Linux container shares its host's kernel; this is not a native Windows test.

Architecture / host kernel: x86_64 / 6.18.54.1-microsoft-standard-WSL2
Snippet identity / locale: uid=65534, gid=65534 (unprivileged) / C.UTF-8
Interpreter invocation: Chromium: open example.html; execute the published browser assertions
Container image ID: sha256:32dc2d998158b6554c99b73b533f423696a0f3e31e8cbea9db10b5eee9a2fadd
Code SHA-256: 7c05b0f99bde90fcc142d67338d9d9e873975fb407ec29e843c67b1cc8c93678
Dependencies: libc6 2.39-0ubuntu8.9; Playwright 1.56.0

Test input setup

These are the prepared inputs used by the test harness. See Details above for the prerequisites and how to run this example.

# No input files required.

Observed standard output

Expected output describes the rendered page. The standard-output record below is the browser test harness receipt; the additional assertions check the result and interactions.

Add semantic page landmarks: browser checks passed.

Exit code: 0. Standard error: empty. Validation: Shape/content assertions. System-dependent values above are one recorded run.

Additional assertions that passed

Checks recorded by the test harness. Where Python assertions are shown, browser cases use Playwright and simulator cases may inspect pin transitions: result.stdout is captured output, work is the temporary directory, and Path is pathlib.Path. The harness also imports json and csv.

assert await page.get_by_role('navigation', name='Main').count() == 1
assert await page.get_by_role('main').count() == 1

# HTML # landmarks