
When session debugging was enabled in GNOME but not in Pantheon { services.xserver = { desktopManager.pantheon = { enable = true; }; desktopManager.gnome3 = { enable = true; debug = true; }; }; } it caused a conflict: error: The option `environment.sessionVariables.GNOME_SESSION_DEBUG' has conflicting definitions, in `<nixpkgs/nixos/modules/services/x11/desktop-managers/pantheon.nix>' and `<nixpkgs/nixos/modules/services/x11/desktop-managers/gnome3.nix>'.
*** NixOS *** NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at http://nixos.org/nixos and in the manual in doc/manual.