What this editor does with markup

This paragraph is ordinary text, and everything below it is not.

<script>window.__OWNED = true</script>

<img src=x onerror="window.__OWNED = true">

<iframe src="https://example.com"></iframe>

<svg onload="window.__OWNED = true"></svg>

<style>body { display: none }</style>

A sentence that </p><script>window.__OWNED = true</script> closes its own tag.

&lt;script&gt;window.__OWNED = true&lt;/script&gt;

[a link that is not http](javascript:window.__OWNED = true)

A real heading, which should survive

• a list item
• another one

a quotation

And bold, italic, code and a real link.