Fumiki Takahashi

TAROSKY INC.

Add iframe block for block editor. 
WordPress editor sometimes cleans up <code>iframe</code> tag if the user is a contributor(single site) or an editor(multi site) who has no capability <a href="https://wordpress.org/support/article/roles-and-capabilities/#unfiltered_html" rel="ugc">unfiltered_html</a>.
This plugin simply add 1 custom block iframe block. That’s all and no config.
<h4>Features</h4>
<ul>
<li><code>iframe</code> tag not escaped.</li>
<li>Responsive supported.</li>
<li>Keep aspect ratio. Default is <code>16:9</code>.</li>
<li>Keep <code>iframe</code> unescaped even in multisite. If you have multiple writers in your site, this might help without any roles-and-capabilities knowledge.</li>
<li>Align full and align wide supported.</li>
</ul>

Taro iframe Block

Add iframe block for your editor. Responsive and keeping aspect ratio.

dbhynds

Lazy load images, YouTube and Vimeo videos, and iframes using <a href="https://github.com/ressio/lazy-load-xt" rel="nofollow ugc">Lazy Load XT</a>.
Lazy Load XT is the fastest, lightest, fully customizable lazy load plugin in the WordPress Plugin Directory.
This plugin works by loading the Lazy Load XT script and replacing the <code>src</code> attributes with <code>data-src</code> when the content of a post or page is loaded on the front end of a WordPress site.

Lazy Load XT

See this image
http://i.imgur.com/PzOIDGI.png
It's my main page's slider, it loads blank when installing this plugin
When the page loads at the first time without any cache, it loads with the browser's default font, then suddenly changed into the site's font. Not just the images in "not seen parts", but also images in the view port load blank. I would say this plugin has a huge potential, but at the moment, as it's not updated, it doesn't function as it advertises despite having 5/5 reviews.



Not really impressive as I thought

Lazy Load images, videos, iframes and more using Lazy Load XT.

Taro iframe Block vs Lazy Load XT