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### Issue Details

* **Electron Version:**
  * 12.0.0-beta.1 to 12.0.0-beta.6
* **Operating System:**
  * Windows 10 (2004) 
* **Last Known Working Electron version:**
  * 11.x.x (all of them)

### Expected Behavior
Click on Menu Item opens the submenu of this item

### Actual Behavior
Clicking on menu set with Menu.setApplicationMenu(Menu.buildFromTemplate(topLevelItems)); is not possible. Pressing "ALT" Highlights the menu but nothing more happens

### To Reproduce
Build Application with menu
shell/browser/ui/views/menu_bar.cc
views::AccessiblePaneView::OnThemeChanged();
  RefreshColorCache();
  UpdateViewColors();
}
void MenuBar::RebuildChildren() {
  RemoveAllChildViews(true);
  for (int i = 0, n = GetItemCount(); i < n; ++i) {
    auto* button =
        new SubmenuButton(menu_model_->GetLabelAt(i), background_color_);
    button->set_tag(i);
    button->SetCallback(base::BindRepeating(&MenuBar::ButtonPressed,
                                            base::Unretained(this),
                                            base::Unretained(button)));
    AddChildView(button);
  }
  UpdateViewColors();
}
void MenuBar::UpdateViewColors() {