On systemd systems you can just either set KEY=VALUE pairs in `/etc/environment` or any file in `/etc/environment.d/` (and technically a few other places [0]).

On systemd systems you can just either set KEY=VALUE pairs in `/etc/environment` or any file in `/etc/environment.d/` (and technically a few other places [0]). In theory it should be relatively easy to write a GUI for it by manually parsing the files. The application restarting part can't really be fixed, since environment variables aren't ever injected to a running process and can only be changed by the process itself (terms and conditions may apply) and even changes during runtime could be ignored since the program itself may have cached some already computed value based on the variable. [0]: https://www.freedesktop.org/software/systemd/man/latest/environment.d.html https://www.freedesktop.org/software/systemd/man/latest/envi...