Regolith On Stage is available for Regolith v1.3.1+ and can be installed on Ubuntu 18.04, 19.10 or 20.04 by adding a PPA and installing the regolith-on-stage package. Adding the PPA will allow you to get the latest updates automatically.

            $ sudo add-apt-repository ppa:gdeflaux/regolith-on-stage
            $ sudo apt install regolith-on-stage