anchor.diff:  
        ${pkgs.glib.dev}/bin/glib-compile-schemas $out/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas/
       '';
  +
  +  nixos-background-info = pkgs.writeTextFile rec {
  +    name = "nixos-background-info";
  +    text = ''
  +      <?xml version="1.0"?>
  +      <!DOCTYPE wallpapers SYSTEM "gnome-wp-list.dtd">
  +      <wallpapers>
  +        <wallpaper deleted="false">
  +          <name>Blobs</name>
  +          <filename>${nixos-background-ligtht.gnomeFilePath}</filename>
  +          <filename-dark>${nixos-background-dark.gnomeFilePath}</filename-dark>
  +          <options>zoom</options>
  +          <shade_type>solid</shade_type>
  +          <pcolor>#3a4ba0</pcolor>
  +          <scolor>#2f302f</scolor>
  +        </wallpaper>
  +      </wallpapers>
  +    '';
  +    destination = "/share/gnome-background-properties/nixos.xml";
  +  };
   
     flashbackEnabled = cfg.flashback.enableMetacity || length cfg.flashback.customSessions > 0;
     flashbackWms = optional cfg.flashback.enableMetacity {
  
positive.code:      chmod -R a+w $out/share/gsettings-schemas/nixos-gsettings-overrides
       cat - > $out/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas/nixos-defaults.gschema.override <<- EOF
         [org.gnome.desktop.background]
         picture-uri='file://${pkgs.nixos-artwork.wallpapers.simple-blue.gnomeFilePath}'
         picture-uri-dark='file://${pkgs.nixos-artwork.wallpapers.simple-dark-gray.gnomeFilePath}'
  
         [org.gnome.desktop.screensaver]
         picture-uri='file://${pkgs.nixos-artwork.wallpapers.simple-dark-gray-bottom.gnomeFilePath}'
  
         ${cfg.favoriteAppsOverride}
  
  
negative.code:       # Adapt from https://gitlab.gnome.org/GNOME/gnome-build-meta/blob/gnome-3-38/elements/core/meta-gnome-core-shell.bst
        environment.systemPackages = with pkgs.gnome; [
          adwaita-icon-theme
          nixos-background-info
          gnome-backgrounds
          gnome-bluetooth
          gnome-color-manager
  