Ayesh Karunaratne

Adds support for embedding Facebook and Instagram posts in Block Editor (Gutenberg) and Classic Editor. This feature was removed in WordPress core due to deprecation of legacy APIs WordPress core used.
Prior to WordPress 5.5.1, WordPress had support to embed Instagram and Facebook photos, videos, notes, quizes, etc in posts created with Block Editor and Classic Editor. However, Facebook removed this legacy API in October 2020, and this plugin implements the new APIs to bring back support for Facebook and Instagram content embedding.
Note that you will need to register a Facebook developer account and create an app to get API credentials that this plugin uses. There is no coding necessary, but an API key needs to be created and set for the plugin.
Detailed setup instructions are available in <a href="https://php.watch/articles/wordpress-facebook-instagram-oembed" rel="nofollow ugc">oEmbed Plus guide at PHP.Watch</a>
This project is not owned, endorsed, or otherwise affiliated with Facebook Inc. or Instagram LLC.

oEmbed Plus

As the title suggests, this is written beautifully and works perfectly.

No bloat.

On-screen links to where you need to go at facebook and documentation.

And the ability to define keys in wp-config make it great for multisite.

Works perfectly, and elegantly coded for MultiSite

Adds support for embedding Facebook and Instagram posts in Block Editor (Gutenberg) and Classic Editor.

johnh10

Broken Link Checker for YouTube is a WordPress plugin that will automatically validate 
YouTube embeds found in your published posts content using the official API.
It does this by extracting video IDs from each post and querying the YouTube 
API to ensure those IDs are still valid. This is a MUST for any video 
site that wants to retain their visitors and not annoy them with broken 
content.
The truth is videos are uploaded and removed frequently – either by the user 
or the site itself for usage violations. If this happens to a video you have 
embedded on your site, your visitors are going to see broken content instead 
of the video they expected. Don’t let that happen.
Quick Summary:
<iframe loading="lazy" class="youtube-player" width="640" height="360" src="https://www.youtube.com/embed/jxc6ioU0WJ0?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>

Broken Link Checker for YouTube

Will automatically validate
YouTube embeds found in your published posts content using the official API.

oEmbed Plus vs Broken Link Checker for YouTube