Greetings!

I am the author of Newspaper, a feed renderer for Greasemonkey.

I suggest to incorporate it, or some features of it, into this script.

https://openuserjs.org/scripts/sjehuda/Newspaper

Great job!

Thanks for an interesting idea. I currently have limited time to work on this script, unfortunately, but could you explain how you envision your suggested functionality would work, since my script works on directory urls, not individual file urls. Are you imagining a directory full of .url or .webloc files that point to RSS feeds, and that selecting one from the sidebar of my script would open the RSS in the preview pane? This won't work, because of CORS issues; the feed url would have to be opened in a new tab instead. Currently my script does allow you to view the contents of a .url or .webloc file itself, and you can click the link or type Cmd/Ctrl + ArrowDown to open it in a new tab. But perhaps you have another idea?

No. Neither of these.

Are you imagining a directory full of .url or .webloc files that point to RSS feeds, and that selecting one from the sidebar of my script would open the RSS in the preview pane?

This might be a possibility, albeit this is not what I suggest.

Just as this script renders MarkDown files, I suggest to render files of type Atom, JSON Feed, OPML, RDF, and RSS.

I am aware that it is rare to store these files, yet it would be interesting to see another, approach, use and style (CSS Stylesheet) of rendering of syndication feeds.

Please. Install "Newspaper", and observe and review it.

OK, I'll bear this in mind, but development won't take place any time soon, especially since it looks like testing and implementing these features would not be simple.