nixos/pantheon: Default to wayland session (#442810)

      - changed-files:

          - any-glob-to-any-file:

              - nixos/modules/services/desktops/pantheon/**/*

              - nixos/modules/services/x11/desktop-managers/pantheon.nix

              - nixos/modules/services/desktop-managers/pantheon.nix

              - nixos/modules/services/x11/display-managers/lightdm-greeters/pantheon.nix

              - nixos/tests/pantheon.nix

              - pkgs/desktops/pantheon/**/*

- GNOME 3 has been upgraded to 3.34. Please take a look at their [Release Notes](https://help.gnome.org/misc/release-notes/3.34) for details.

- If you enable the Pantheon Desktop Manager via [services.xserver.desktopManager.pantheon.enable](options.html#opt-services.xserver.desktopManager.pantheon.enable), we now default to also use [ Pantheon's newly designed greeter ](https://blog.elementary.io/say-hello-to-the-new-greeter/). Contrary to NixOS's usual update policy, Pantheon will receive updates during the cycle of NixOS 20.03 when backwards compatible.

- If you enable the Pantheon Desktop Manager via `services.xserver.desktopManager.pantheon.enable`, we now default to also use [ Pantheon's newly designed greeter ](https://blog.elementary.io/say-hello-to-the-new-greeter/). Contrary to NixOS's usual update policy, Pantheon will receive updates during the cycle of NixOS 20.03 when backwards compatible.

- By default zfs pools will now be trimmed on a weekly basis. Trimming is only done on supported devices (i.e. NVME or SSDs) and should improve throughput and lifetime of these devices. It is controlled by the `services.zfs.trim.enable` varname. The zfs scrub service (`services.zfs.autoScrub.enable`) and the zfs autosnapshot service (`services.zfs.autoSnapshot.enable`) are now only enabled if zfs is set in `config.boot.initrd.supportedFilesystems` or `config.boot.supportedFilesystems`. These lists will automatically contain zfs as soon as any zfs mountpoint is configured in `fileSystems`.

- mate-wayland-session 1.28.4 is now using the default wayfire decorator instead of firedecor, thus `services.xserver.desktopManager.mate.enableWaylandSession` is no longer shipping firedecor. If you are experiencing broken window decorations after upgrade, backup and remove `~/.config/mate/wayfire.ini` and re-login.

- Due to [deprecation of gnome-session X11 support](https://blogs.gnome.org/alatiera/2025/06/08/the-x11-session-removal/), `services.desktopManager.pantheon` now defaults to pantheon-wayland session. The X11 session will be removed before gnome-session 49 lands.

- `services.gitea` supports sending notifications with sendmail again. To do this, activate the parameter `services.gitea.mailerUseSendmail` and configure SMTP server.

- `networking.wireless.networks.<name>` now has an option to specify SSID, hence allowing duplicated SSID setup. The BSSID option is added along side with this.

All of Pantheon is working in NixOS and the applications should be available, aside from a few [exceptions](https://github.com/NixOS/nixpkgs/issues/58161). To enable Pantheon, set

```nix

{ services.xserver.desktopManager.pantheon.enable = true; }

{ services.desktopManager.pantheon.enable = true; }

```

This automatically enables LightDM and Pantheon's LightDM greeter. If you'd like to disable this, set

```nix

Wingpanel and Switchboard work differently than they do in other distributions, as far as using plugins. You cannot install a plugin globally (like with {option}`environment.systemPackages`) to start using it. You should instead be using the following options:

  - [](#opt-services.xserver.desktopManager.pantheon.extraWingpanelIndicators)

  - [](#opt-services.xserver.desktopManager.pantheon.extraSwitchboardPlugs)

  - [](#opt-services.desktopManager.pantheon.extraWingpanelIndicators)

  - [](#opt-services.desktopManager.pantheon.extraSwitchboardPlugs)

to configure the programs with plugs or indicators.

let

  cfg = config.services.xserver.desktopManager.pantheon;

  cfg = config.services.desktopManager.pantheon;

  serviceCfg = config.services.pantheon;

  nixos-gsettings-desktop-schemas = pkgs.pantheon.elementary-gsettings-schemas.override {

    maintainers = teams.pantheon.members;

  };

  imports = [

    (lib.mkRenamedOptionModule

      [ "services" "xserver" "desktopManager" "pantheon" ]

      [ "services" "desktopManager" "pantheon" ]

    )

  ];

  options = {

    services.pantheon = {

    };

    services.xserver.desktopManager.pantheon = {

    services.desktopManager.pantheon = {

      enable = mkOption {

        type = types.bool;

        default = false;

  config = mkMerge [

    (mkIf cfg.enable {

      services.xserver.desktopManager.pantheon.sessionPath = utils.removePackagesByName [

      services.desktopManager.pantheon.sessionPath = utils.removePackagesByName [

        pkgs.pantheon.pantheon-agent-geoclue2

      ] config.environment.pantheon.excludePackages;

      # Without this, elementary LightDM greeter will pre-select non-existent `default` session

      # https://github.com/elementary/greeter/issues/368

      services.displayManager.defaultSession = mkDefault "pantheon";

      services.displayManager.defaultSession = mkDefault "pantheon-wayland";

      programs.dconf.profiles.user.databases = [

        {

          settings."io/elementary/greeter" = {

            last-session-type = "pantheon-wayland";

          };

        }

      ];

      environment.extraInit = ''

        ${concatMapStrings (p: ''