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HTML 

              
                <h1>ARIA Heading Level Test</h1>

<p>
  That was an <code>&lt;h1&gt;</code>, no ARIA. From here it's going to get a bit weird. <a href="https://validator.w3.org/nu/?showsource=yes&doc=https%3A%2F%2Fcdpn.io%2Fpen%2Fdebug%2FXWQvRvO" target="_top">Validator</a>. Used in my post <cite><a href="https://adrianroselli.com/2024/05/level-setting-heading-levels.html" target="_top">Level-Setting Heading Levels</a></cite>.
</p>

<hr>

<dl>
  <dt>A: <code>role="heading"</code>, no <code>aria-level</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd>Narrator: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt class="buggy">Safari: no level</dt>
      <dd>VoiceOver / macOS: no level</dd>
      <dd>VoiceOver: no level</dd>
    </dl>
  </dd>
  <dt>B: <code>role="heading"</code>, <code>aria-level="1"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 1</dt>
      <dd>NVDA: 1</dd>
      <dd>Orca: 1</dd>
      <dd>Narrator: 1</dd>
      <dd>TalkBack: 1</dd>
      <dt>Chrome: 1</dt>
      <dd>JAWS: 1</dd>
      <dd>NVDA: 1</dd>
      <dd>TalkBack: 1</dd>
      <dt>Edge: 1</dt>
      <dd>Narrator: 1</dd>
      <dt>Safari: 1</dt>
      <dd>VoiceOver / macOS: 1</dd>
      <dd>VoiceOver: 1</dd>
    </dl>
  </dd>
  <dt>C: <code>role="heading"</code>, <code>aria-level="2"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd>Narrator: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt>Safari: 2</dt>
      <dd>VoiceOver / macOS: 2</dd>
      <dd>VoiceOver: 2</dd>
    </dl>
  </dd>
  <dt>D: <code>role="heading"</code>, <code>aria-level="3"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 3</dt>
      <dd>NVDA: 3</dd>
      <dd>Orca: 3</dd>
      <dd>Narrator: 3</dd>
      <dd>TalkBack: 3</dd>
      <dt>Chrome: 3</dt>
      <dd>JAWS: 3</dd>
      <dd>NVDA: 3</dd>
      <dd>TalkBack: 3</dd>
      <dt>Edge: 3</dt>
      <dd>Narrator: 3</dd>
      <dt>Safari: 3</dt>
      <dd>VoiceOver / macOS: 3</dd>
      <dd>VoiceOver: 3</dd>
    </dl>
  </dd>
  <dt>E: <code>role="heading"</code>, <code>aria-level="4"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 4</dt>
      <dd>NVDA: 4</dd>
      <dd>Orca: 4</dd>
      <dd>Narrator: 4</dd>
      <dd>TalkBack: 4</dd>
      <dt>Chrome: 4</dt>
      <dd>JAWS: 4</dd>
      <dd>NVDA: 4</dd>
      <dd>TalkBack: 4</dd>
      <dt>Edge: 4</dt>
      <dd>Narrator: 4</dd>
      <dt>Safari: 4</dt>
      <dd>VoiceOver / macOS: 4</dd>
      <dd>VoiceOver: 4</dd>
    </dl>
  </dd>
  <dt>F: <code>role="heading"</code>, <code>aria-level="5"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 5</dt>
      <dd>NVDA: 5</dd>
      <dd>Orca: 5</dd>
      <dd>Narrator: 5</dd>
      <dd>TalkBack: 5</dd>
      <dt>Chrome: 5</dt>
      <dd>JAWS: 5</dd>
      <dd>NVDA: 5</dd>
      <dd>TalkBack: 5</dd>
      <dt>Edge: 5</dt>
      <dd>Narrator: 5</dd>
      <dt>Safari: 5</dt>
      <dd>VoiceOver / macOS: 5</dd>
      <dd>VoiceOver: 5</dd>
    </dl>
  </dd>
  <dt>G: <code>role="heading"</code>, <code>aria-level="6"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 6</dt>
      <dd>NVDA: 6</dd>
      <dd>Orca: 6</dd>
      <dd>Narrator: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt>Safari: 6</dt>
      <dd>VoiceOver / macOS: 6</dd>
      <dd>VoiceOver: 6</dd>
    </dl>
  </dd>
  <dt>H: <code>role="heading"</code>, <code>aria-level="7"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 7</dt>
      <dd>NVDA: 7</dd>
      <dd>Orca: 7</dd>
      <dd>Narrator: 7</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Chrome: 7</dt>
      <dd class="buggy">JAWS: 2</dd>
      <dd>NVDA: 7</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Edge: 7</dt>
      <dd>Narrator: 7</dd>
      <dt>Safari: 7</dt>
      <dd>VoiceOver / macOS: 7</dd>
      <dd>VoiceOver: 7</dd>
    </dl>
  </dd>
  <dt>I: <code>role="heading"</code>, <code>aria-level="8"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 8</dt>
      <dd>NVDA: 8</dd>
      <dd>Orca: 8</dd>
      <dd>Narrator: 8</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Chrome: 8</dt>
      <dd class="buggy">JAWS: 2</dd>
      <dd>NVDA: 8</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Edge: 8</dt>
      <dd>Narrator: 8</dd>
      <dt>Safari: 8</dt>
      <dd>VoiceOver / macOS: 8</dd>
      <dd>VoiceOver: 8</dd>
    </dl>
  </dd>
  <dt>J: <code>role="heading"</code>, <code>aria-level="9"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 9</dt>
      <dd>NVDA: 9</dd>
      <dd>Orca: 9</dd>
      <dd>Narrator: 9</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Chrome: 9</dt>
      <dd class="buggy">JAWS: 2</dd>
      <dd>NVDA: 9</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Edge: 9</dt>
      <dd>Narrator: 9</dd>
      <dt>Safari: 9</dt>
      <dd>VoiceOver / macOS: 9</dd>
      <dd>VoiceOver: 9</dd>
    </dl>
  </dd>
  <dt>K: <code>role="heading"</code>, <code>aria-level="10"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 10</dt>
      <dd>NVDA: 10</dd>
      <dd>Orca: 10</dd>
      <dd class="buggy">Narrator: not recognized as heading</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt class="buggy">Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt class="buggy">Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt>Safari: 10</dt>
      <dd>VoiceOver / macOS: 10</dd>
      <dd>VoiceOver: 10</dd>
    </dl>
  </dd>
  <dt>L: <code>role="heading"</code>, <code>aria-level="20"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 20</dt>
      <dd>NVDA: 20</dd>
      <dd>Orca: 20</dd>
      <dd class="buggy">Narrator: not recognized as heading</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt class="buggy">Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt class="buggy">Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt>Safari: 20</dt>
      <dd>VoiceOver / macOS: 20</dd>
      <dd>VoiceOver: 20</dd>
    </dl>
  </dd>
  <dt>M: <code>&lt;h6&gt;</code>, <code>aria-level="7"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 7</dt>
      <dd>NVDA: 7</dd>
      <dd>Orca: 7</dd>
      <dd>Narrator: 7</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Chrome: 7</dt>
      <dd class="buggy">JAWS: 2</dd>
      <dd>NVDA: 7</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt>Edge: 7</dt>
      <dd>Narrator: 7</dd>
      <dt>Safari: 7</dt>
      <dd>VoiceOver / macOS: 7</dd>
      <dd>VoiceOver: 7</dd>
    </dl>
  </dd>
  <dt>N: <code>&lt;h6&gt;</code>, <code>aria-level="30"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 30</dt>
      <dd>NVDA: 30</dd>
      <dd>Orca: 30</dd>
      <dd class="buggy">Narrator: not recognized as heading</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt class="buggy">Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt class="buggy">Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt>Safari: 30</dt>
      <dd>VoiceOver / macOS: 30</dd>
      <dd>VoiceOver: 30</dd>
    </dl>
  </dd>
  <dt>O: <code>&lt;h6&gt;</code>, <code>aria-level="0"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 6</dt>
      <dd>NVDA: 6</dd>
      <dd>Orca: 6</dd>
      <dd class="buggy">Narrator: announces O, P, Q as one heading at 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt>Safari: 6</dt>
      <dd>VoiceOver / macOS: 6</dd>
      <dd>VoiceOver: 6</dd>
    </dl>
  </dd>
  <dt>P: <code>&lt;h6&gt;</code>, <code>aria-level="-1"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 6</dt>
      <dd>NVDA: 6</dd>
      <dd>Orca: 6</dd>
      <dd class="buggy">Narrator: announces O, P, Q as one heading at 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt class="buggy">Safari: 4294967295</dt>
      <dd>VoiceOver / macOS: 6</dd>
      <dd>VoiceOver: 6</dd>
    </dl>
  </dd>
  <dt>Q: <code>&lt;h6&gt;</code>, <code>aria-level="hammer"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 6</dt>
      <dd>NVDA: 6</dd>
      <dd>Orca: 6</dd>
      <dd class="buggy">Narrator: announces O, P, Q as one heading at 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt>Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt>Safari: 6</dt>
      <dd>VoiceOver / macOS: 6</dd>
      <dd>VoiceOver: 6</dd>
    </dl>
  </dd>
  <dt>R: <code>role="heading"</code>, <code>aria-level="0"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd class="buggy">Narrator: announces R, S, T as one heading at 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt class="buggy">Safari: no level</dt>
      <dd class="buggy">VoiceOver / macOS: no level</dd>
      <dd class="buggy">VoiceOver: no level</dd>
    </dl>
  </dd>
  <dt>S: <code>role="heading"</code>, <code>aria-level="-1"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd class="buggy">Narrator: announces R, S, T as one heading at 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt class="buggy">Safari: 4294967295</dt>
      <dd class="buggy">VoiceOver / macOS: no level</dd>
      <dd class="buggy">VoiceOver: no level</dd>
    </dl>
  </dd>
  <dt>T: <code>role="heading"</code>, <code>aria-level="hammer"</code></dt>
  <dd>
    <dl>
      <dt>Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd class="buggy">Narrator: announces R, S, T as one heading at 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt>Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt class="buggy">Safari: no level</dt>
      <dd class="buggy">VoiceOver / macOS: no level</dd>
      <dd class="buggy">VoiceOver: no level</dd>
    </dl>
  </dd>
  <dt>U: <code>role="heading"</code>, <code>aria-level="2147483647"</code> (2<sup>31</sup>&minus;1)</dt>
  <dd>
    <dl>
      <dt>Firefox: 2147483647</dt>
      <dd>NVDA: 2147483647</dd>
      <dd>Orca: 2147483647</dd>
      <dd class="buggy">Narrator: not recognized as heading</dd>
      <dd class="buggy">TalkBack: no level</dd>
      <dt class="buggy">Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt class="buggy">Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt>Safari: 2147483647</dt>
      <dd>VoiceOver / macOS: 2147483647</dd>
      <dd>VoiceOver: 2147483647</dd>
    </dl>
  </dd>
  <dt>V: <code>role="heading"</code>, <code>aria-level="2147483648"</code> (2<sup>31</sup>)</dt>
  <dd>
    <dl>
      <dt class="buggy">Firefox: 2</dt>
      <dd>NVDA: 2</dd>
      <dd>Orca: 2</dd>
      <dd>Narrator: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt class="buggy">Chrome: 2</dt>
      <dd>JAWS: 2</dd>
      <dd>NVDA: 2</dd>
      <dd>TalkBack: 2</dd>
      <dt class="buggy">Edge: 2</dt>
      <dd>Narrator: 2</dd>
      <dt class="buggy">Safari: no level</dt>
      <dd class="buggy">VoiceOver / macOS: no level</dd>
      <dd class="buggy">VoiceOver: no level</dd>
    </dl>
  </dd>
  <dt>W: <code>&lt;h6&gt;</code>, <code>aria-level="2147483648"</code> (2<sup>31</sup>)</dt>
  <dd>
    <dl>
      <dt class="buggy">Firefox: 6</dt>
      <dd>NVDA: 6</dd>
      <dd>Orca: 6</dd>
      <dd>Narrator: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt class="buggy">Chrome: 6</dt>
      <dd>JAWS: 6</dd>
      <dd>NVDA: 6</dd>
      <dd>TalkBack: 6</dd>
      <dt class="buggy">Edge: 6</dt>
      <dd>Narrator: 6</dd>
      <dt class="buggy">Safari: 6</dt>
      <dd class="buggy">VoiceOver / macOS: 6</dd>
      <dd class="buggy">VoiceOver: 6</dd>
    </dl>
  </dd>
</dl>

<hr>

<p>Aggregated Results</p>
<ul>
  <li>Browsers overall handle headings through level 9.</li>
  <li>Firefox and Safari/macOS support heading levels up to 2<sup>31</sup>&minus;1.</li>
  <li>Chrome only supports up to 9, falling back to 2 for all values greater than 9.</li>
  <li>Edge only supports up to 9, falling back to 2 for all values greater than 9.</li>
  <li>Safari/macOS does not like a <code>-1</code> value, but it seems to have no impact on a user.</li>
  <li>NVDA and Orca take their values from the browser.</li>
  <li>JAWS takes (or matches) its values from the browser until those values are greater than 6, falling back to 2.</li>
  <li>Narrator treats any headings (via HTML or ARIA) with a level greater than 9 as no longer a heaing.</li>
  <li>Narrator treats level 0 and following non-numeric headings as a single heading at level 2.</li>
  <li>TalkBack does not like levels above 6, announcing no level with Firefox and leaning on Chrome's bug to announce 2.</li>
  <li>VoiceOver is pleasantly consistent between macOS and iPadOS.</li>
  <li>Bugs and VoiceOver aside, invalid level values make the browser fall back to level 2 on an element roled up to a heading (VoiceOver/macOS announces no level) or the heading level of a heading element.</li>
</ul>

<!-- <p>Verdict</p>
<ul>
  <li>Until JAWS (and probably TalkBack) fixes its bug, probably don't do any heading levels higher than 6.</li>
  <li>And then, until Chrome (and probably Narrator) fixes its bug, probably don't do any heading levels higher than 9.</li>
  <li>Using a heading (probably <code>&lt;h6&gt;</code>) with <code>aria-level</code> is safer than roling up another element with <code>aria-level</code>.</li>
  <li>If you need more than two billion one-hundred forty-seven million four-hundred eighty-three thousand six-hundred forty-seven heading levels, you may need to hire a copywriter.</li>
</ul> -->

<hr>

<div role="heading">Test A</div>

<div role="heading" aria-level="1">Test B</div>

<div role="heading" aria-level="2">Test C</div>

<div role="heading" aria-level="3">Test D</div>

<div role="heading" aria-level="4">Test E</div>

<div role="heading" aria-level="5">Test F</div>

<div role="heading" aria-level="6">Test G</div>

<div role="heading" aria-level="7">Test H</div>

<div role="heading" aria-level="8">Test I</div>

<div role="heading" aria-level="9">Test J</div>

<div role="heading" aria-level="10">Test K</div>

<div role="heading" aria-level="20">Test L</div>

<h6 aria-level="7">Test M</h6>

<h6 aria-level="30">Test N</h6>

<h6 aria-level="0">Test O</h6>

<h6 aria-level="-1">Test P</h6>

<h6 aria-level="hammer">Test Q</h6>

<div role="heading" aria-level="0">Test R</div>

<div role="heading" aria-level="-1">Test S</div>

<div role="heading" aria-level="hammer">Test T</div>

<div role="heading" aria-level="2147483647">Test U</div>

<div role="heading" aria-level="2147483648">Test V</div>

<h6 aria-level="2147483648">Test W</h6>


<!--
<ul>
  <li><a href="https://www.w3.org/TR/wai-aria-1.0/states_and_properties#aria-level" target="_top"><code>aria-level</code> in ARIA 1.0</a></li>
  <li><a href="https://www.w3.org/TR/wai-aria-1.1/#aria-level" target="_top"><code>aria-level</code> in ARIA 1.1</a></li>
  <li><a href="https://www.w3.org/TR/wai-aria/#aria-level" target="_top"><code>aria-level</code> in ARIA 1.2</a></li>
  <li>ARIA WG <a href="https://www.w3.org/2023/02/23-aria-minutes#t02" target="_top">declines to impose a 1&ndash;6 limit on <code>aria-level</code></a>, 23 February 2023</li>
  <li><a href="https://w3c.github.io/aria/#aria-level" target="_top"><code>aria-level</code> in ARIA 1.3 Draft</a></li>
  <li>Core AAM 1.2 <a href="https://www.w3.org/TR/core-aam-1.2/#ariaLevelHeading" target="_top">§ 4.5.2.57 aria-level on heading</a></li>
  <li>Core AAM CR <a href="https://w3c.github.io/core-aam/#ariaLevelHeading" target="_top">§ 4.5.2.57 aria-level on heading</a></li>
  <li>Core AAM 1.2 <a href="https://www.w3.org/TR/core-aam-1.2/#role-map-heading" target="_top">§ 4.4.3.33 heading</a></li>
  <li>Core AAM CR <a href="https://w3c.github.io/core-aam/#role-map-heading" target="_top">§ 4.4.3.33 heading</a></li>
  <li>Scott O'Hara's <a href="https://scottaohara.github.io/tests/html-headings/6plus.html" target="_top">Testing heading levels beyond 6</a></li>
  <li>ARIA issue <a href="https://github.com/w3c/aria/issues/1757" target="_top">#1757 Update aria-level on heading mapping to reflect UIA limitation</a> (closed resolved)</li>
  <li>Chromium issue <a href="https://issues.chromium.org/issues/41468140" target="_top">ARIA aria-level values over 9 don't work</a> (closed resolved)</li>
  <li>JAWS bug <a href="https://github.com/FreedomScientific/standards-support/issues/301" target="_top">#301 aria-level&gt;6 is not output correctly for headings</a></li>
  <li>JAWS bug <a href="https://github.com/FreedomScientific/standards-support/issues/814" target="_top">#814 JAWS does not support aria-level on h1-h6</a></li>
  <li>Steve Faulkner's <a href="https://stevefaulkner.github.io/AT-browser-tests/test-files/h7-h10.html" target="_top">h7-h9 via aria-level elements</a> test page</li>
  <li>A11y Support <a href="https://a11ysupport.io/tests/tech__aria__headings-above-6" target="_top">Test: ARIA headings greater than level 6</a></li>
</ul>
-->
<!-- <dl>
  <dt>Firefox 125</dt>
  <dd>NVDA 2024.1</dd>
  <dd>Orca on Ubuntu 22.04.2 LTS</dd>
  <dd>Narrator Win11 23H2</dd>
  <dd>TalkBack 14.2</dd>
  <dt>Chrome 124</dt>
  <dd>JAWS 2024.2403.3</dd>
  <dd>NVDA 2024.1</dd>
  <dd>TalkBack 14.2</dd>
  <dt>Edge 124</dt>
  <dd>Narrator Win11 23H2</dd>
  <dt>Safari 17.4</dt>
  <dd>VoiceOver macOS 14.4.1</dd>
  <dd>VoiceOver iPadOS 17.4.1</dd>
  <dd></dd>
</dl> -->
<!--
<ul>
 <li class="good">Good, meaning it works well for everyone;</li>
 <li class="fine">Fine, but could be improved;</li>
 <li class="caution">Caution, has issues but may be ok in some cases;</li>
 <li class="buggy">Buggy, probably avoid.</li>
</ul>
-->
!

CSS 

              
                html {
  color-scheme: light dark;
}

@supports (font: -apple-system-body) and (not (-webkit-touch-callout: default)) {
  :root {
    font-size: 100%;
  }
}

body {
  font: -apple-system-body;
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto,
    Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  line-height: 1.4;
}

/* h1 + p + dl {
  column-count: 2;
  column-gap: 4em;
} */

h6 {
  margin: initial;
  font: inherit;
  /*   padding: inherit; */
}

code,
pre,
tt,
kbd {
  font-family: "Consolas", "Andale Mono", "Lucida Sans Typewriter",
    "Roboto Mono", "SF Mono", "Courier New", Courier, monospace;
  font-weight: normal;
  font-variant-ligatures: none;
  opacity: .8;
}

dl:nth-of-type(2) dt::before {
  /*   content: "Test "; */
}

dt {
  font-weight: bold;
}

dt:not(dl dl dt):not(:first-child) {
  font-weight: bold;
  margin-block-start: 1.5em;
}

sup {
  line-height: 0;
  font-size: 80%;
}

.good::before {
  content: "\01F44D ";
  display: inline;
}

.fine::before {
  content: "\02714 ";
  display: inline;
}

.caution::before {
  content: "‽ ";
  font-weight: bold;
  font-size: 125%;
  line-height: 0;
  display: inline;
}

.buggy::before {
  content: "\0274c ";
  content: "\026A0  ";
  font-weight: normal;
  /*   color: light-dark(#a00, #bb0); */
  display: inline-block;
  border-radius: 50%;
  width: 1.2em;
  height: 1.2em;
  text-align: center;
  /*   outline: 1px solid #f00; */
  line-height: 1;
  /*   font-size: 60%; */
  background-color: light-dark(#a00, #bb0);
  color: light-dark(#fff, #000);
  margin-inline-end: 0.25em;
  text-indent: 0;
}

.buggy {
  /*   margin-inline-start: -1.5em; */
  text-indent: -1.45em;
}
!

JS
!
999px

Console