Blackbam

Create, manage and view snapshots of any post (or custom post type) whenever you want. Like user-managed revisions with a lot of useful functionality.
Features: 
* Create snapshots of any post type including all metadata at any point manually as a secure history and backup of your posts 
* Uses the standard WordPress posts table (like revisions) 
* Uses a custom post status (and therefore works for any post type) 
* Easy snapshot management meta box 
* Create Snapshots comfortably in the publish post box 
* Choose which post types you want to enable the snapshots feature for
PHP Developer API: 
 pos_create_snapshot_from($post_id): Creates a new snapshot for a given post ID 
 pos_delete_snapshot($snap_id): Delete a snapshot by its ID 
 pos_get_latest_snapshot($post_id): Returns the ID of the latest snapshot for a given post ID 
 pos_get_plainview_url($snap_id): Get the URL to the plain snapshot view
This Plugin is sponsored by ready2order GmbH, the company which is producing Austria’s best point-of-sale system. Visit us at https://www.ready2order.com/.
NOTE: The use of a custom post status in WordPress is still in beta. The developers of this plugin are in no possible case responsible for any data loss. 
If you want to be sure nothing happens, backup your database on a regular basis. You should do it anyway.

Post Snapshots

Everything works as expected and I did not hear any compaints yet.

On our live website it has been working great since two months now

Create, manage and view snapshots of any post (or custom post type) whenever you want. Like user-managed revisions with a lot of useful functionality.

webshrinker

This plugin will allow you to automatically show previews of external websites when a user hovers over a link in your posts. 
It’s designed to work “out-of-the-box” and no changes should be needed on your part to make it work. 
However, if you are familiar with CSS, you can apply “link previews” to links in other places in WordPress site by specifying any CSS selector that you want.
A free or paid <a href="https://www.webshrinker.com" rel="nofollow ugc">Web Shrinker</a> account is required as you will need a service API key.
<iframe class="youtube-player" width="640" height="360" src="https://www.youtube.com/embed/1xGf00XQSH8?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"></iframe>

Web Shrinker – Website Link Preview Thumbnails

Enhance your post links by enabling a popup preview thumbnail image of the destination website

Post Snapshots vs Web Shrinker – Website Link Preview Thumbnails