These events are emitted for every navigation request which isn't really efficient. Also upstream has removed the observers that provide these details as part of network servification https://chromium-review.googlesource.com/c/chromium/src/+/805008 and https://chromium-review.googlesource.com/c/chromium/src/+/786320. We are removing it as a part of chromium 66 upgrade.

Proposed alternative: Users can use the [webRequest](https://github.com/electron/electron/blob/master/docs/api/web-request.md) module which provides similar navigation details on a subscription basis.
atom/browser/api/atom_api_web_contents.cc
v8::Locker locker(isolate());
  v8::HandleScope handle_scope(isolate());
  devtools_web_contents_.Reset();
  Emit("devtools-closed");
}
#if defined(TOOLKIT_VIEWS)
void WebContents::ShowAutofillPopup(content::RenderFrameHost* frame_host,
                                    const gfx::RectF& bounds,
                                    const std::vector<base::string16>& values,
                                    const std::vector<base::string16>& labels) {
  bool offscreen = IsOffScreen() || (embedder_ && embedder_->IsOffScreen());
  CommonWebContentsDelegate::ShowAutofillPopup(offscreen, frame_host, bounds,
                                               values, labels);
}
#endif
bool WebContents::OnMessageReceived(const IPC::Message& message) {