As in topic. API currently offers fixed ratio only for Mac but not for Windows
shell/browser/native_window_views.cc
const gfx::AcceleratedWidget accelerated_widget = GetAcceleratedWidget();
  content::DesktopMediaID::Id window_handle = content::DesktopMediaID::kNullId;
  content::DesktopMediaID::Id aura_id = content::DesktopMediaID::kNullId;
#if defined(OS_WIN)
  window_handle =
      reinterpret_cast<content::DesktopMediaID::Id>(accelerated_widget);
#elif defined(OS_LINUX)
  window_handle = static_cast<uint32_t>(accelerated_widget);
#endif
  aura::WindowTreeHost* const host =
      aura::WindowTreeHost::GetForAcceleratedWidget(accelerated_widget);
  aura::Window* const aura_window = host ? host->window() : nullptr;
  if (aura_window) {
    aura_id = content::DesktopMediaID::RegisterNativeWindow(
                  content::DesktopMediaID::TYPE_WINDOW, aura_window)
                  .window_id;
  }
  
  
  content::DesktopMediaID result = content::DesktopMediaID(
      content::DesktopMediaID::TYPE_WINDOW, window_handle);
  
  
  
  result.window_id = aura_id;
  return result;
}
gfx::AcceleratedWidget NativeWindowViews::GetAcceleratedWidget() const {