Method is_scene_open

editor/editor_node.cpp:4328–4336

}

bool EditorNode::is_scene_open(const String &p_path) {
	for (int i = 0; i < editor_data.get_edited_scene_count(); i++) {
		if (editor_data.get_scene_path(i) == p_path) {
			return true;
		}
	}

	return false;
}

bool EditorNode::is_multi_window_enabled() const {
	return !SceneTree::get_singleton()->get_root()->is_embedding_subwindows() && !EDITOR_GET("interface/editor/single_window_mode") && EDITOR_GET("interface/multi_window/enable");