Wayland : Add extra compat variables thanks to Fox.

module/Sway.nix

@@ -16,14 +16,18 @@ in {
 	];
 
 	services.gnome.gnome-keyring.enable = lib.mkForce false;
-	environment.systemPackages = with pkgs; [
-		grim slurp                     # Screenshot.
-		mako                           # Notification system.
-		networkmanagerapplet           # Internet configuration.
-		pamixer pavucontrol pulseaudio # Audio.
-		playerctl                      # Multimedia controls.
-		script
-	];
+	environment = {
+		systemPackages = with pkgs; [
+			grim slurp                     # Screenshot.
+			mako                           # Notification system.
+			networkmanagerapplet           # Internet configuration.
+			pamixer pavucontrol pulseaudio # Audio.
+			playerctl                      # Multimedia controls.
+			script                         # My custom Sway shell scripts.
+		];
+
+		variables.XDG_CURRENT_DESKTOP = "sway";
+	};
 
 	programs.sway = {
 		enable = true;

module/desktop/App.nix

@@ -62,6 +62,9 @@ in {
 
 			# Proton.
 			WINEFSYNC = "1";
+
+			# GTK apps compat.
+			GTK_CSD = 0;
 		};
 	};
 

module/desktop/Wayland.nix

@@ -1,5 +1,20 @@
 { pkgs, ... }: {
-	environment.systemPackages = with pkgs; [
-		wl-clipboard
-	];
+	environment = {
+		systemPackages = with pkgs; [
+			wl-clipboard # CLI clipboard support.
+		];
+
+		variables = {
+			# Compatibility variables.
+			ECORE_EVAS_ENGINE                   = "wayland_egl";
+			ELM_ENGINE                          = "wayland_egl";
+			GDK_BACKEND                         = "wayland";
+			MOZ_ENABLE_WAYLAND                  = "1";
+			QT_QPA_PLATFORM                     = "wayland-egl";
+			QT_WAYLAND_DISABLE_WINDOWDECORATION = "1";
+			SAL_USE_VCLPLUGIN                   = "gtk3";
+			SDL_VIDEODRIVER                     = "wayland";
+			_JAVA_AWT_WM_NONREPARENTING         = "1";
+		};
+	};
 }

module/desktop/firefox/default.nix

@@ -9,10 +9,7 @@
 	mkBookmark = name: url: { inherit name url; };
 in {
 	# Disable profile switching on rebuild.
-	environment.variables = {
-		MOZ_LEGACY_PROFILES = "1";
-		MOZ_ENABLE_WAYLAND  = "1";
-	};
+	environment.variables.MOZ_LEGACY_PROFILES = "1";
 
 	programs.firefox = {
 		enable  = true;