Babel includes JSX processing.
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<details open> <summary>Here is the top level summary</summary> <p>In the details is an important video</p> <iframe frameborder="0" height="315" src="https://www.youtube.com/embed/t2oVUxTV4WA" width="560"></iframe> <details> <summary>Here is a nested summary</summary> <p>In the nested details is another important video</p> <iframe frameborder="0" height="315" src="https://www.youtube.com/embed/HEVD3j_sYzw" width="560"></iframe> </details> </details>
Also see: Tab Triggers