As in topic. API currently offers fixed ratio only for Mac but not for Windows
shell/browser/native_window_views.cc
params.wm_class_name = base::ToLowerASCII(name);
  params.wm_class_class = name;
#endif
  widget()->Init(std::move(params));
  bool fullscreen = false;
  options.Get(options::kFullscreen, &fullscreen);
  std::string window_type;
  options.Get(options::kType, &window_type);
#if defined(USE_X11)
  if (!features::IsUsingOzonePlatform()) {
    
    window_state_watcher_ = std::make_unique<WindowStateWatcher>(this);
    
    bool use_dark_theme = false;
    if (options.Get(options::kDarkTheme, &use_dark_theme) && use_dark_theme) {
      SetGTKDarkThemeEnabled(use_dark_theme);
    }
  }
#endif
#if defined(OS_LINUX)
  if (parent)
    SetParentWindow(parent);
#endif
#if defined(USE_X11)
  if (!features::IsUsingOzonePlatform()) {
    
    
    std::vector<x11::Atom> state_atom_list;
    bool skip_taskbar = false;