marckula

This plugin registers Haiku Deck ( haikudeck.com ) as an oEmbed content provider and adds it to the whitelist, allowing all users to use this provider.
Here’s more information about embeds for WordPress 
https://codex.wordpress.org/Embeds

Haiku Deck for WordPress

Register Haiku Deck as an oEmbed content provider

INN Labs

Pym.js Embeds provides shortcode and Gutenberg block wrappers for embedding responsive iframes using <a href="http://blog.apps.npr.org/pym.js/" rel="nofollow ugc">Pym.js</a>, developed by the NPR Visuals Team. Embedded content resizes vertically to match its container’s width.
AMP compatibility is provided by the <a href="https://wordpress.org/plugins/amp/" rel="ugc">official AMP plugin</a>.
<h3>Pym.js Resources from NPR</h3>
You may also want to look at NPR’s Pym.js resources:
<ul>
<li><a href="http://blog.apps.npr.org/pym.js/" rel="nofollow ugc">Pym.js homepage</a></li>
<li><a href="https://github.com/nprapps/pym.js/" rel="nofollow ugc">Pym.js repo on GutHub/nprapps</a></li>
</ul>

Pym.js Embeds

A WordPress block and shortcode for embedding iframes that are responsive horizontally and vertically, using the NPR Visuals Team's Pym.js.

Haiku Deck for WordPress vs Pym.js Embeds