Similar to NetNewsWire on macOS, NewsFlash is a clean, stable, fast, free, no-clutter and no-nonsense RSS/Atom newsfeed reader for Linux. You can read articles in the application or open them in the web browser of your choice. It syncs new posts quickly and I haven’t had any issues with it getting stuck the way I had with Communique (before the latter stopped working entirely!)
It’s an app, not a service, so it’s not tracking you or inserting ads. That also means there’s no web version. But it can sync over several web-based newsreaders like FreshRSS, Nextcloud News (which is what I use it with), Inoreader and more. So you can keep track of your subscriptions and read/unread articles across devices.
NewsFlash is an entirely rewritten application by the author of the now-discontinued FeedReader, who describes it as the “spiritual successor” to the older application.
Built for GNOME, but I’ve got the Flatpak working just fine on KDE Plasma and LxQt.