QuiteRSS is a great desktop RSS feed reader for GNU/Linux and it is, in LinuxReviews' opinion, the best one. It is built using the Qt framwork.
Look and feel
QuiteRSS is very strait-forward and easy to use. It supports folders and sub-folders for your feeds and you can drag and drop feeds to neatly organize them.
QuiteRSS works great with the default out-of-the-box settings. It is highly configurable if you do not like those. You can choose colors, fonts and font sizes and a lot of other things in it's
All in all it's a great RSS feed reader for GNU/Linux desktops and our RSS feed reader comparison rates it as the best.
Installation on Ubuntu is done by the usual
apt-get install quiterss. Installing on Fedora is not as easy since you will get a broken package as of Fedora 30 so you have to compile it yourself.
The QuiteRSS homepage is at quiterss.org.
Compiling it from git
The QuiteRSS on Fedora 30 is broken as of 2019. It produces a "Segmentation fault (core dumped)" in in QAction::setText(QString const&) () at /lib64/libQtGui.so.4. QuiteRSS works best when built with the newer Qt5. That is what the package uses on Ubuntu and you do not need to bother with compiling it yourself on that OS.
Here's have you install QuiteRSS from source on Fedora assuming you have the basic development packages installed (git, qmake, etc).
sudo dnf -y install sqlite-devel mkdir src;cd src git clone https://github.com/QuiteRSS/quiterss.git cd quiterss/ mkdir cmake_build;cd cmake_build qmake-qt5 SYSTEMQTSA=1 CONFIG+=release PREFIX=/usr/local ../QuiteRSS.pro make -j12 sudo -c 'make install'