Text highlighter and submission

I'm looking to create a web page highlighter that will show a few paragraphs on screen but will then allow a person to highlight good lines in green and bad lines in red by highlighting a section of the text and then clicking a button (or typing a number, as is the case in thunderbird). I'd then like to be able to essentially submit this text to a background engine of some kind.

I can't find any code that does this. So far I've looked through many examples in different programming languages:

• html5
• jqueryscript.net
• crystal programming language
• wordpress plugins
• chrome plugins
• wxpython
• d3js

The closest I can find is: https://www.jqueryscript.net/demo/Text-Highlight-Plugin-jQuery-Marker/ or https://www.jqueryscript.net/demo/Facebook-Like-Hashtag-Highlighting-Plugin-with-jQuery-hashtags-js/ but this is actually not doing what I want. The highlighting needs to be live/interactive with a submission to the backend.

There are a number of really nice looking chrome highlighters but again none of them can be stored and submitted to a backend page.

The other thing that I was wanting is that this would be inside a user login area so that it can be stored for different documents for different users, but this is putting the 'cart before the horse'.

If I had my perference I'd have something simple that works with a python backend and wordpress. I have 30 years of mainly backend programming experience in C++, python, java, fortran but have no idea how to do this. I've used d3js in the past and found it pretty easy, but this type of "live text highlighter/annotator" doesn't seem to be available in any engine and I now wonder if this is because its too difficult to solve.