/// <summary>
        /// Adds children window to list binded to its parent in structure manager.
        /// </summary>
        public static void Add_Children_Window(IMainWindow_Children children_Window)
        {
            Add_Children(children_Window);

            if (children_Window is IOptionsWindow_Show options_Window)
            {
                Options_Windows_List.Add(options_Window);
            }
        }
        /// <summary>
        /// Removes given children window out of structure manager.
        /// </summary>
        static void Remove_Children_Window(IMainWindow_Children Children_Window)
        {
            if (Children_Window is IOptionsWindow_Show options_Window)
            {
                Options_Windows_List.Remove(options_Window);
            }

            Remove_children(Children_Window);
        }