code: func Init() error {
  	rawMtx.Lock()
  	defer rawMtx.Unlock()
  
  	if termRaw {
  		return ErrAlreadyInitialized
  	}
  
  	// switch mode
  	err := termbox.Init()
  	if err != nil {
  		return err
  	}
  
  	bg = termbox.ColorDefault
  	fg = termbox.ColorDefault
  	termbox.HideCursor()
  	termbox.SetInputMode(termbox.InputAlt) // this may need to become variable
  	_ = termbox.Clear(bg, bg)
  	maxX, maxY = termbox.Size()
  	_ = termbox.Flush()
  
  	// see if we need to launch the key handler
  	if !keyHandler {
  		go initKeyHandler()
  		keyHandler = true
  	}
  
  	termRaw = true // we are now in raw mode
  
  	return nil
  }
docs: // Init switches the terminal to raw mode and commences managed window mode.
  // This function shall be called prior to any ttk calls.