diff --git a/src/UI/Dialogs/WindowOpacityDialog.gd b/src/UI/Dialogs/WindowOpacityDialog.gd
index 1a9c8136c..b61573779 100644
--- a/src/UI/Dialogs/WindowOpacityDialog.gd
+++ b/src/UI/Dialogs/WindowOpacityDialog.gd
@@ -5,6 +5,7 @@ onready var spinbox: SpinBox = $HBoxContainer2/SpinBox
 
 
 func _on_WindowOpacityDialog_about_to_show() -> void:
+	OS.window_per_pixel_transparency_enabled = true
 	hslider.editable = !OS.window_fullscreen
 	spinbox.editable = hslider.editable
 
diff --git a/src/UI/TopMenuContainer.gd b/src/UI/TopMenuContainer.gd
index 8c818da05..44fd0012d 100644
--- a/src/UI/TopMenuContainer.gd
+++ b/src/UI/TopMenuContainer.gd
@@ -575,7 +575,7 @@ func _toggle_fullscreen() -> void:
 	OS.window_fullscreen = !OS.window_fullscreen
 	window_menu.set_item_checked(Global.WindowMenu.FULLSCREEN_MODE, OS.window_fullscreen)
 	if OS.window_fullscreen:  # If window is fullscreen then reset transparency
-		window_opacity_dialog.set_window_opacity(1.0)
+		window_opacity_dialog.set_window_opacity(100.0)
 
 
 func image_menu_id_pressed(id: int) -> void: