Here is how to quickly reproduce the bug: Electron fiddle: https://gist.github.com/josephernest/f3db7d319af407b2dcef04c7c1c514ee

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I have a `#topleft` red title bar containing multiple "tab" buttons that should fill all the available space *except* a `#topright` blue block.  
It is possible to move the main Electron window by click-and-dragging on `#topleft`'s red background, thanks to `-webkit-app-region: drag;`. This works.

[![enter image description here][1]][1]

**Problems**: 

1. clicks on `#topright` are ignored: `alert()` is not triggered  (same problem for child elements of this block)
2. `#topright span:hover { background-color: black; }` is ignored 
3. `#topright { -webkit-app-region: no-drag; }` is ignored: we can still move the window by click-and-dragging on `#topright` whereas it should not

However if we run the same HTML code *in a browser*, all is working correctly.

  [1]: https://i.stack.imgur.com/ZZPsJ.png
shell/browser/native_browser_view_views.cc
auto new_view_size = view->size();
    new_view_size.set_width(new_view_size.width() + width_delta);
    new_view_size.set_height(new_view_size.height() + height_delta);
    view->SetSize(new_view_size);
  }
  auto new_view_bounds = view->bounds();
  if (flags & kAutoResizeHorizontal) {
    new_view_bounds.set_width(new_window.width() /
                              auto_horizontal_proportion_width_);
    new_view_bounds.set_x(new_window.width() /
                          auto_horizontal_proportion_left_);
  }
  if (flags & kAutoResizeVertical) {
    new_view_bounds.set_height(new_window.height() /
                               auto_vertical_proportion_height_);
    new_view_bounds.set_y(new_window.height() / auto_vertical_proportion_top_);
  }
  if ((flags & kAutoResizeHorizontal) || (flags & kAutoResizeVertical)) {
    view->SetBoundsRect(new_view_bounds);
  }
}
void NativeBrowserViewViews::ResetAutoResizeProportions() {
  if (auto_resize_flags_ & AutoResizeFlags::kAutoResizeHorizontal) {
    auto_horizontal_proportion_set_ = false;
  }
  if (auto_resize_flags_ & AutoResizeFlags::kAutoResizeVertical) {
    auto_vertical_proportion_set_ = false;
  }
}
void NativeBrowserViewViews::SetBounds(const gfx::Rect& bounds) {