Removed a lot of desktop entries, to clean up Menu. Added a boot splash screen.

boot-splash.nix

@@ -0,0 +1,23 @@
+{ config, lib, pkgs, ... }:
+{
+boot = {
+    loader.timeout = 0;
+    # silence first boot output
+    consoleLogLevel = 3;
+    initrd.verbose = false;
+    initrd.systemd.enable = true;
+    kernelParams = [
+        "quiet"
+        "splash"
+        "intremap=on"
+        "boot.shell_on_fail"
+        "udev.log_priority=3"
+        "rd.systemd.show_status=auto"
+    ];
+
+    # plymouth, showing after LUKS unlock
+    plymouth.enable = true;
+    plymouth.font = "${pkgs.hack-font}/share/fonts/truetype/Hack-Regular.ttf";
+    plymouth.logo = "${pkgs.nixos-icons}/share/icons/hicolor/128x128/apps/nix-snowflake.png";
+};
+}