code: func (m *Monitor) Size() (width, height float64) {
  	var mode *glfw.VidMode
  	mainthread.Call(func() {
  		mode = m.monitor.GetVideoMode()
  	})
  	width = float64(mode.Width)
  	height = float64(mode.Height)
  	return
  }
docs: // Size returns the resolution of the Monitor in pixels.