Pure collapsible element

We can create an expandable element with pure HTML tags as following:

<details>
    <summary>Title</summary>
    <!--
    The hidden content that will be shown when 
    clicking the `summary` tag.
    -->
</details>

I often use the tags when including a long error log on GitHub:

<details>
    <summary>Error log</summary>
    <pre><code><!-- Full log here --></code></pre>
</details>