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<h4><strong>13. Top-level numbered heading in source</strong></h4>
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<h5><strong>13.1 First subsection heading</strong></h5>
<p>Where it activates: ...</p>
<h5><strong>13.2 Second subsection heading</strong></h5>
<p>Where it activates: ...</p>
<h5><strong>13.3 Third subsection heading</strong></h5>
<p>Where it activates: ...</p>
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