Fix wrong viewport transparent-bg

servers/visual/visual_server_viewport.cpp

@@ -505,7 +505,7 @@ void VisualServerViewport::viewport_set_transparent_background(RID p_viewport, b
 	ERR_FAIL_COND(!viewport);
 
 	VSG::storage->render_target_set_flag(viewport->render_target, RasterizerStorage::RENDER_TARGET_TRANSPARENT, p_enabled);
-	viewport->transparent_bg = true;
+	viewport->transparent_bg = p_enabled;
 }
 
 void VisualServerViewport::viewport_set_global_canvas_transform(RID p_viewport, const Transform2D &p_transform) {