this was mistake

modules/nixos/desktop/window-managers/plasma.nix

@@ -1,12 +0,0 @@
-{ pkgs, ... }:
-{
-  services.desktopManager.plasma6.enable = true;
-
-  xdg.portal.extraPortals = [ pkgs.kdePackages.xdg-desktop-portal-kde ];
-  xdg.portal.config.plasma.default = [ "kde" ];
-
-  environment.systemPackages = with pkgs; [
-    kdePackages.plasma-browser-integration
-    kdePackages.kwalletmanager
-  ];
-}