title: Hidden markdown text on GitHub
body: <p>Is there anything in markdown syntax specifically on GitHub to support hidden text?</p>
  <p>I just want to put some to-do notes in <code>README.md</code> for myself, not to be visible.</p>
  <hr />
  <p><strong>EXTRAS</strong></p>
  <p>As a tribute to the great answer by Tamas, and what's also asked a lot of times, below is an example of how to write foldable sections within MD files:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;details&gt;
  &lt;summary&gt;&lt;b&gt;My section header in bold&lt;/b&gt;&lt;/summary&gt;
  
  Any folded content here. It requires an empty line just above it.
  
  &lt;/details&gt;
  </code></pre>