anchor.diff:        [ manual.manual help ]
         ++ optional config.programs.man.enable manual.manpages;
   
  -    boot.extraTTYs = mkIf cfg.showManual ["tty${cfg.ttyNumber}"];
  +    boot.extraTTYs = mkIf cfg.showManual ["tty${toString cfg.ttyNumber}"];
   
       systemd.services = optionalAttrs cfg.showManual
         { "nixos-manual" =
  
positive.code:     };
  
      services.nixosManual.ttyNumber = mkOption {
        default = "8";
        description = ''
          Virtual console on which to show the manual.
        '';
  
negative.code:             { ExecStart = "${cfg.browser} ${entry}";
                StandardInput = "tty";
                StandardOutput = "tty";
                TTYPath = "/dev/tty${toString cfg.ttyNumber}";
                TTYReset = true;
                TTYVTDisallocate = true;
                Restart = "always";
  