chromium/content/test/data/accessibility/aria/aria-level.html

<!--
@BLINK-ALLOW:hierarchicalLevel*
@MAC-ALLOW:AXDisclosing
@MAC-ALLOW:AXDisclosureLevel
@MAC-ALLOW:AXIndex
@WIN-ALLOW:level:*
@WIN-ALLOW:EXPANDED
@WIN-DENY:name=''
@AURALINUX-ALLOW:level:*
@AURALINUX-ALLOW:expand*
-->
<!DOCTYPE html>
<html>
<body>

<h1 aria-level="2">Level 2</h1>
<h2 aria-level="9">Level 9</h2>
<h1 aria-level="20">Level 1</h1>
<h3>Level 3</h3>

<div role="heading" aria-level="3">Level 3</div>
<h2 role="heading" aria-level="4">Level 4</h2>
<h5 role="heading">Level 5</h5>

<!-- aria-level for tree items -->
<div role="tree">
  <div role="treeitem" aria-expanded="true">
    Tree item at level 1
    <div role="group">
      <div role="treeitem">Tree item at level 2</div>
      <div role="treeitem" aria-level="0">
        Tree item at level 2, aria-level is 0
      </div>
    </div>
  </div>
  <div role="treeitem" aria-level="3">
    Tree item at level 3
  </div>
  <div role="treeitem" aria-level="20">
    Tree item at level 20
  </div>
  <div role="treeitem" aria-level="1">
    Tree item at level 1
  </div>
  <div role="treeitem" aria-level="0">
    Tree item at level 1
  </div>
  <div role="treeitem" aria-level="-1">
    Tree item at level 1
  </div>
</div>

<table role="treegrid">
  <tr role="row" aria-level="1">
    <td role="gridcell">Cell at level 1</td>
  </tr>
  <tr role="row" aria-level="2">
    <td role="gridcell">Cell at level 2</td>
  </tr>
</table>

<!-- aria-level for list items -->
<div role="listitem">List item at level 1</div>
<div role="listitem" aria-level="3">List item at level 3</div>
<div role="list">
  <div role="listitem" aria-level="2">List item at level 2</div>
  <div role="list">
    <div role="listitem">List item at level 2</div>
    <div role="listitem" aria-level="7">List item at level 7</div>
  </div>
</div>
</body>
</html>