Fix heading-order accessibility violation on Live Transcript slide

[Copilot]

Axe flagged <h3 class="small">Transcript</h3> on the Live Transcript slide for violating heading-order semantics. The H3 was redundant with the slide's H2 title and didn't represent a meaningful subsection.

Changes

index.html

• Removed redundant <h3 class="small">Transcript</h3> from Live Transcript slide

Before:

<section class="slide" id="demo-transcript" aria-label="Live Transcript">
  <h2>Live Transcript</h2>
  <div class="transcript">
    <h3 class="small">Transcript</h3>  <!-- Redundant -->
    <div id="whisper-transcript" class="transcript-box" ...></div>
  </div>
</section>

After:

<section class="slide" id="demo-transcript" aria-label="Live Transcript">
  <h2>Live Transcript</h2>
  <div class="transcript">
    <div id="whisper-transcript" class="transcript-box" ...></div>
  </div>
</section>

scripts/test-heading-order.js (new)

• Validates heading hierarchy doesn't skip levels (h1→h3 without h2)
• Integrated into npm test suite

Heading hierarchy

• Before: H1 → H2 → H2 → ... → H2 → H3 ← (redundant) → H2 → H3 → H3
• After: H1 → H2 → H2 → ... → H2 → H2 → H3 → H3 ✓

Note: H3 headings on the Combined slide remain as they represent distinct subsections (Demo | Transcript columns).

Screenshot

No visual changes—fix improves semantic structure for screen readers.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• dequeuniversity.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)
• https://storage.googleapis.com/chromium-browser-snapshots/Linux_x64/869685/chrome-linux.zip
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node install.js (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Accessibility issue: Heading levels should only increase by one on /whisper-slides/</issue_title>
<issue_description>## What
An accessibility scan flagged the element <h3 class="small">Transcript</h3> on https://mgifford.github.io/whisper-slides/ because heading levels should only increase by one. Learn more about why this was flagged by visiting https://dequeuniversity.com/rules/axe/4.11/heading-order?application=playwright.

To fix this, ensure the order of headings is semantically correct.

Specifically:

Fix any of the following:

• Heading order invalid

Acceptance Criteria

• The specific axe violation reported in this issue is no longer reproducible.
• The fix MUST meet WCAG 2.1 guidelines OR the accessibility standards specified by the repository or organization.
• A test SHOULD be added to ensure this specific axe violation does not regress.
• This PR MUST NOT introduce any new accessibility issues or regressions.

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Accessibility issue: Heading levels should only increase by one on /whisper-slides/ #2

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[mgifford]

Looks good.