- Electron version: 0.37.6
- Operating system: Windows 10

In VSCode, in order to support screen readers while editing text, we set the contents of a `<textarea>` to the contents of the line and lines surrounding the cursor and we mirror the editor selection in the `<textarea>` via `setSelectionRange`.

Chromium is not the fastest when it comes to setting large amounts of text :) (such as > 10,000 characters) and basically stalls all the time. Apparently, Electron already has some knowledge about when a screen reader is attached to the main process window (in C++ code). Is it possible to expose this as a getter + event when it first happens in the `electron` API.

We could then maintain this costly `<textarea>` sync only when really needed.

atom/browser/browser.cc
bool prevent_default = false;
  FOR_EACH_OBSERVER(BrowserObserver,
                    observers_,
                    OnBeforeQuit(&prevent_default));
  return !prevent_default;
}
void Browser::OnWindowCloseCancelled(NativeWindow* window) {
  if (is_quiting_)
    
    
    is_quiting_ = false;
}
void Browser::OnWindowAllClosed() {
  if (is_exiting_)
    Shutdown();
  else if (is_quiting_)
    NotifyAndShutdown();
  else
    FOR_EACH_OBSERVER(BrowserObserver, observers_, OnWindowAllClosed());
}
}