title: Semantically correct way to add titles and subtitles for non-sectioning elements (HTML)?
body: <p>What html elements are most appropriate to add titles and subtitles to components which are not related to explicit or implicit website sections, e.g. table or figure captions, cards etc.?</p>
  
  <p>According to W3, headings are not recommended for subtitles:</p>
  
  <blockquote>
    <p>h1–h6 elements must not be used to markup subheadings, subtitles, alternative titles and taglines unless intended to be the heading for a new section or subsection.</p>
  </blockquote>
  
  <p>But it also seems that heading tags are not to be used outside of section context:</p>
  
  <blockquote>
    <p>Heading content defines the header of a section (whether explicitly marked up using sectioning content elements, or implied by the heading content itself).</p>
  </blockquote>
  
  <p>Does this mean that usage of <code>&lt;h4&gt;</code> in the example below is not correct and <code>&lt;div&gt;</code>'s must be used instead?</p>
  
  <pre><code> &lt;figcaption&gt;
       &lt;h4&gt;Title&lt;/h4&gt;
       &lt;div class="byline"&gt;Byline&lt;/div&gt;
       &lt;p&gt;Some description.&lt;/p&gt;
   &lt;/figcaption&gt;
  </code></pre>