Here is a port on the mozilla addons page… Seems legit but no source code on how it is making the actual build…

I currently use Feedly (its proprietary though)… I have in mind switching to my own instance of FreshRSS which looks awesome and has its mobile compatible apps too.

I would also like to mention two little tricks that made my life easier with RSS:

• First RSSHub: it allows you to made a RSS feed out of almost anything! RSS can be awesome…
• Second, in GitHub if you append ‘.atom’ to any relases of a repostory you get a RSS feed for releases (which I use to track different releases) for example for lemmy https://github.com/LemmyNet/lemmy/releases.atom

Hope this helps!

Have been using Mlem for a while now… But I find it worth to try and provide feedback!