Embed PDF on LMS article

Hi, is there a way to embed PDF on article doctype for LMS? Or embed it as suggested here How to embed a PDF in HTML without the ability to download

<title>Example on how to embed Google Drive PDF inside website</title>
<meta charset="UTF-8" />
<div id="app">

Adding html editor on article doctype does not allow me to show html generated page, let alone embed a PDF.

iframe tag also removed, writing </iframe> will become &lt;/iframe&gt;