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
content::WebContents* web_contents,
    net::SSLCertRequestInfo* cert_request_info,
    net::ClientCertIdentityList client_certs,
    std::unique_ptr<content::ClientCertificateDelegate> delegate) {
  if (!client_certs.empty() && delegate_) {
    delegate_->SelectClientCertificate(web_contents, cert_request_info,
                                       std::move(client_certs),
                                       std::move(delegate));
  }
  return base::OnceClosure();
}
bool AtomBrowserClient::CanCreateWindow(
    content::RenderFrameHost* opener,
    const GURL& opener_url,
    const GURL& opener_top_level_frame_url,
    const url::Origin& source_origin,
    content::mojom::WindowContainerType container_type,
    const GURL& target_url,
    const content::Referrer& referrer,