Safari Technology Preview now supports dark mode via `@media (prefers-color-scheme: dark)` in CSS media queries. 

Same should be supported in Electron apps to enable automatic light/dark mode switching.

shell/browser/atom_browser_client.cc
AtomBrowserClient::CreateSpeechRecognitionManagerDelegate() {
  return new AtomSpeechRecognitionManagerDelegate;
}
content::TtsControllerDelegate* AtomBrowserClient::GetTtsControllerDelegate() {
#if BUILDFLAG(ENABLE_TTS)
  return TtsControllerDelegateImpl::GetInstance();
#else
  return nullptr;
#endif
}
void AtomBrowserClient::OverrideWebkitPrefs(content::RenderViewHost* host,