Ryan

Adds a section to the bottom of your pages and posts listing any external 
links.
Only links starting with http or https are included so ftp, mailto, etc 
will not be included in the list; although it would be pretty trival to 
edit the plugin to allow them to. Likewise any links that start with your 
blog URL are also excluded.
For more information, you can visit <a href="http://www.nutt.net/tag/link-footnotes/" rel="nofollow ugc">Nutt.net</a>

Link Footnotes

Adds a footnotes section to your posts with any external links

K. Adam White

defomicron

Civil Footnotes is a WordPress plugin for adding footnotes on your blog. Civil Footnotes parses your posts for notes wrapped in ((double parenthesis)), then extracts that parenthesized text into a footnote list at the end of the post.
There are many solutions for managing footnotes within your WordPress website, but Civil Footnotes distinguishes itself from the rest with a simple, readable plain text syntax that works whether you’re using the WordPress block editor, a Markdown editor, or the classic editor plugin.
The majority of Civil Footnotes’ formatting is taken from the blog <a href="https://daringfireball.net/" rel="nofollow ugc">Daring Fireball</a>, which first debuted this style of footnotes <a href="http://daringfireball.net/2005/07/footnotes" rel="nofollow ugc">in 2005</a>. The key difference is the addition of a <code>title</code> attribute to the footnote reference in the text which permits sighted mouse users to efficiently read the note by hovering their cursor over the reference number.
<h4>Credits</h4>
Civil Footnotes was originally created by <a href="https://defomicron.net/" rel="nofollow ugc">Austin Sweeney</a> and is currently maintained by <a href="https://www.kadamwhite.com" rel="nofollow ugc">K. Adam White</a>.
<h3>License & Attribution</h3>
This plugin is licensed under the terms of the <a href="./license.txt" rel="nofollow ugc">GNU General Public License</a> (or “GPL”). It is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Civil Footnotes

Add footnotes to your site using a simple, easy-to-read inline syntax ((by wrapping footnote content with double-parentheses)).

Link Footnotes vs Civil Footnotes