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* Electron version: 2.0.0-beta.3
* Operating system: Ubuntu 16.04.04 LTS

### Expected behavior

App menu should be visible

### Actual behavior

App menu is invisible

### How to reproduce

- Run `electron`
- Observe that the app menu is invisible. It is still possible to open submenus.

![screenshot from 2018-03-14 17-01-18](https://user-images.githubusercontent.com/19880051/37415303-7296c25e-27ab-11e8-8284-d213c8bf5230.png)

atom/browser/native_window_views.cc
if (menu_model == nullptr) {
    
    accelerator_table_.clear();
    GetFocusManager()->UnregisterAccelerators(this);
    
#if defined(USE_X11)
    global_menu_bar_.reset();
#endif
    SetMenuBarVisibility(false);
    menu_bar_.reset();
    return;
  }
  RegisterAccelerators(menu_model);
#if defined(USE_X11)
  if (!global_menu_bar_ && ShouldUseGlobalMenuBar())
    global_menu_bar_.reset(new GlobalMenuBarX11(this));
  
  if (global_menu_bar_ && global_menu_bar_->IsServerStarted()) {
    global_menu_bar_->SetMenu(menu_model);
    return;
  }
#endif
  
  if (!has_frame())