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
atom::api::WebContents::Type val) {
    using Type = atom::api::WebContents::Type;
    std::string type = "";
    switch (val) {
      case Type::BACKGROUND_PAGE:
        type = "backgroundPage";
        break;
      case Type::BROWSER_WINDOW:
        type = "window";
        break;
      case Type::BROWSER_VIEW:
        type = "browserView";
        break;
      case Type::REMOTE:
        type = "remote";
        break;
      case Type::WEB_VIEW:
        type = "webview";
        break;
      case Type::OFF_SCREEN:
        type = "offscreen";
        break;
      default:
        break;
    }
    return mate::ConvertToV8(isolate, type);
  }
  static bool FromV8(v8::Isolate* isolate,