Fix evaluation after merge of #11450.

nixos/modules/services/x11/window-managers/fluxbox.nix

···
   ###### interface
   options = {
     services.xserver.windowManager.fluxbox.enable = mkEnableOption "fluxbox";
+  };
 
   ###### implementation
   config = mkIf cfg.enable {

nixos/modules/services/x11/window-managers/openbox.nix

···
 {lib, pkgs, config, ...}:
 
+with lib;
 let
   inherit (lib) mkOption mkIf;
   cfg = config.services.xserver.windowManager.openbox;
···
 {
   options = {
     services.xserver.windowManager.openbox.enable = mkEnableOption "oroborus";
+  };
 
   config = mkIf cfg.enable {
     services.xserver.windowManager = {

nixos/modules/services/x11/window-managers/wmii.nix

···
 { config, lib, pkgs, options, modulesPath, ... }:
 
+with lib;
 let
   inherit (lib) mkOption mkIf singleton;
   cfg = config.services.xserver.windowManager.wmii;

nixos/modules/services/x11/window-managers/xmonad.nix

···
 {pkgs, lib, config, ...}:
 
+with lib;
 let
   inherit (lib) mkOption mkIf optionals literalExample;
   cfg = config.services.xserver.windowManager.xmonad;