WPKube

The plugin restores the <code>Title</code> field (that was removed from WordPress 4.2) in the insert link popup box and adds a new <code>Add rel="nofollow" to link</code> checkbox to it.
Gutengerg (Block Editor) Note: At the moment it’s not possible to add the functionality to Gutenberg, it’s a different system from the classic editor and it does not have a hook/filter which allows adding custom settings. As soon as it becomes possible to add the functionality to Gutenberg we will update the plugin.
This plugin has been adopted and maintained by <a href="https://www.wpkube.com/" rel="nofollow ugc">WPKube</a>, a popular WordPress resource site, where you can find guides on <a href="https://www.wpkube.com/category/wordpress-plugins/" rel="nofollow ugc">WordPress plugins</a>, <a href="https://www.wpkube.com/best-wordpress-hosting/" rel="nofollow ugc">WordPress Hosting</a>, and more.

Title and Nofollow For Links (Classic Editor)

I just installed this on WP 4.9, and it works like a charm. I ended up adding HTML Class manipulation as well, by coping the code in the JS file that added the title field.

Works Well

works with wp 5.2.1

Helpful tool

The plugin adds a title and a rel="nofollow" checkbox to the insert link popup box. Only for Classic Editor, NOT Block Editor.

WakkerMedia

Wakker Media Newsletter Checkout Checkbox is a quick solution for adding a newsletter checkbox on the Woocommerce Checkout Page. This plugin needs the Newsletter plugin by Stefano Lissa and Woocommerce by Woothemes.
This plugin adds a checkbox for receiving a newsletter from the Newsletter plugin by Stefano Lissa on the Checkout page by Woocommerce. It uses the settings which are added by the Newsletter plugin Subscription Steps (From the Admin menu: Newsletter – Subscription Steps). 
How to use?
Install the Newsletter plugin by Stefano Lissa and Woocommerce by Woothemes and Wakker Media Checkout Checkbox. Activate the plugins.
Adjust the settings on the page Subscription Steps (admin menu: Newsletter – Subscription Steps):
<pre><code>For adding the checkbox on the checkout page, enable: Subscription on registration
 (Choose: “Yes, show the option” or “Yes, show the option already checked”)
Type something like: “Receive Newsletter” for Check box label
</code></pre>
All Done!!
<h3>Arbitrary section</h3>
<h3>A brief Markdown Example</h3>
Ordered list:
<ol>
<li>Adds Newsletter Checkbox on Woocommerce Checkout page</li>
</ol>

Wakker Media Newsletter Checkout Checkbox

Wakker Media Newsletter Checkout Checkbox adds a newsletter checkbox on the Woocommerce Checkout Page.

Title and Nofollow For Links (Classic Editor) vs Wakker Media Newsletter Checkout Checkbox