diff --git a/nix-os/shell.nix b/nix-os/shell.nix
index 08ab4fb..2975c9b 100644
--- a/nix-os/shell.nix
+++ b/nix-os/shell.nix
@@ -42,7 +42,7 @@ in
     scrollback_lines 10000
     window_border_width 0.5
     window_padding_width 3
-    ${if config.services.xserver.desktopManager.gnome.enable then "hide_window_decorations yes" else null}
+    ${if config.services.xserver.desktopManager.gnome.enable then "hide_window_decorations yes" else ""}
     background_opacity 0.8
     dynamic_background_opacity yes
   '';