Plain HTML not supported ? Iframe issue

[vitorpiovezam]

I'm trying to include this iframe to my post, but not working.

<iframe height="265" style="width: 100%;" scrolling="no" title="svg filling sample" src="https://codepen.io/vitorpiovezam/embed/RwwrWBN?height=265&theme-id=dark&default-tab=html,result" frameborder="no" allowtransparency="true" allowfullscreen="true">
  See the Pen <a href='https://codepen.io/vitorpiovezam/pen/RwwrWBN'>svg filling sample</a> by Vitor Goncalves Piovezam
  (<a href='https://codepen.io/vitorpiovezam'>@vitorpiovezam</a>) on <a href='https://codepen.io'>CodePen</a>.
</iframe>

You can test in showdown demo site, http://demo.showdownjs.com/.

[vitorpiovezam]

Solved using ngx-markdown