tranquility-reader-webextensions VS tidy-html5

Another robust solution is Tranquility reader which exists as an extension and has better accuracy than Readability at the expense of speed.

https://github.com/ushnisha/tranquility-reader-webextensions

So I included the tidy libraries in my project.

Maybe look into HTML Tidy. It's job is to clean up HTML and convert legacy code to modern form, so it knows about DTDs. You might be able to pass it some options to get what you want.

I've always used tidy for HTML/XML formatting jobs.

Personally I use command that switches the file type to html, and then formats it with tidy. It assumes you're pasting into a new buffer.

I use tidy.

So I installed HTML tidy.

Prune instructs the parser to remove any elements within the extracted article block that look superfluous. This can result in false positives, so we tend to disable it when we've gone to the trouble of creating site-specific extraction rules.

Tidy determines if the source HTML should be cleaned up first with HTML Tidy - https://github.com/htacg/tidy-html5. If you're parsing the source HTML with an HTML 5 parser, as we are now, it shouldn't be necessary any more (I think we actually ignore it now). We used it more before when we relied on libxml parsing, which often trips up on modern HTML.