lukaiser

ILAnnotations allows you to select a text in a blog post and add your comment to it. 
The plugin uses the standard comments engine of WordPress, so all other comment plugins should work just fine with it. 
Shortcodes are used to mark the highlighted text. This allows you to still edit a post and move stuff around without losing the annotations.

ILAnnotations

Annotate any text in a blog post and add a comment to it.

Luis Rodrigues

Fragmentions were proposed by Kevin Marks in a 2014 <a href="http://www.kevinmarks.com/fragmentions.html" rel="nofollow ugc">blog post</a> as a better alternative to hyperlinking using fragments. Fragmentions use <code>##</code> to match words or phrases in a document.
In the following example, clicking “TL;DR” would jump to the <code></code> element containing “Life, Liberty and the pursuit of Happiness”:
<pre><code><article>
 
 <a href="##pursuit">TL;DR</a>
 

 
 When in the Course of human events, it becomes necessary for one people
 to dissolve the political bands which have connected them with another,
 and to assume among the powers of the earth, the separate and equal
 station to which the Laws of Nature and of Nature’s God entitle them, a
 decent respect to the opinions of mankind requires that they should
 declare the causes which impel them to the separation.
 

 
 We hold these truths to be self-evident, that all men are created
 equal, that they are endowed by their Creator with certain unalienable
 Rights, that among these are Life, Liberty and the pursuit of
 Happiness.
 
</article>
</code></pre>
This plugin relies on <a href="http://www.jonathantneal.com/" rel="nofollow ugc">Jonathan Neal</a>‘s <a href="https://github.com/chapmanu/fragmentions" rel="nofollow ugc">Fragmentions script</a>.
<h3>Licenses</h3>
Jonathan Neal’s Fragmentions script is licensed under a CC0 1.0 Universal License:
Public Domain Dedication
The person(s) who associated a work with this deed has dedicated the work to the public domain by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.
In no way are the patent or trademark rights of any person affected by CC0, nor are the rights that other persons may have in the work or in how the work is used, such as publicity or privacy rights.
Unless expressly stated otherwise, the person(s) who associated a work with this deed makes no warranties about the work, and disclaims liability for all uses of the work, to the fullest extent permitted by applicable law.
When using or citing the work, you should not imply endorsement by the author or the affirmer.
This is a human-readable summary of the Legal Code (<a href="https://creativecommons.org/publicdomain/zero/1.0/" rel="nofollow ugc">read the full text</a>).

Fragmentions

Fragmentions allow linking to document sections on WordPress sites using words or phrases.

ILAnnotations vs Fragmentions