The big new RetroArch 1.6.2 release is imminent, and it will bring some big changes and improvements.
Right out of the gates, here is something that a lot of Linux users have been requesting for decades - a distribution-agnostic way of installing RetroArch on Linux. With Flatpak, this is possible, and this version is available right now!
Read RobLoach's article on this for more information -
https://www.libretro.com/index.php/retroarch-with-flatpak/