kayla: force chrome onto the GTK backend via --ui-toolkit

hosts/FredOS-Kayla.nix

@@ -51,16 +51,6 @@
     # Chrome falls back to stock light Adwaita while everything else is dark.
     programs.dconf.enable = true;
 
-    # ...and point Chrome at GTK rather than its own frame. There is no policy
-    # for this — it's a profile pref — so seed it via Chrome's supported
-    # initial_preferences hook, which is copied into a profile at *creation*.
-    # Fresh profile only: an existing one keeps whatever it already has, and
-    # she can flip it by hand under Settings → Appearance → Theme.
-    # 0 = Classic, 1 = GTK, 2 = Qt.
-    environment.etc."opt/chrome/initial_preferences".text = builtins.toJSON {
-      extensions.theme.system_theme = 1;
-    };
-
     # Stylix's chromium target is a *managed policy* (BrowserThemeColor written
     # to /etc/opt/chrome/policies), which is what makes Chrome say "your
     # administrator has set a default theme" and greys out the appearance
@@ -69,7 +59,12 @@
     stylix.targets.chromium.enable = false;
 
     environment.systemPackages = with pkgs; [
-      google-chrome
+      # Chrome picks its toolkit from the desktop environment, and under KDE
+      # that's the Qt backend (hence the libqt{5,6}_shim.so it ships) — which
+      # is what's drawing the odd decorations. --ui-toolkit overrides that
+      # detection, so it uses GTK, i.e. the adw-gtk3 theme stylix already
+      # writes. No manual trip through Settings → Appearance.
+      (google-chrome.override { commandLineArgs = "--ui-toolkit=gtk"; })
       spotify
       vesktop
       faugus-launcher