override func viewDidLoad() {
  super.viewDidLoad()

  webView.navigationDelegate = self
  
  // Prepare the cashier URL
  let rawUrl = "<YOUR CASHIER URL WITHOUT '#' TAG IN THE END>"
  // CashierHelper.update will throw an exception if rawUrl already contains '#'
  let finalUrl = try? CashierHelper.update(url: rawUrl, with: [.qr, .card]) ?? cashierUrl
  
  // Setup web view and the rest of the view controller...
  
  webView.load(URLRequest(url: finalUrl))

  // Call this line after the webView is part of the view hierarchy
  CashierHelper.connect(to: webView, viewController: self)
}

extension WebViewController: WKNavigationDelegate {
    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        do {
            if let url = navigationAction.request.url?.absoluteString, try NuveiCashierHelper.handleURL(url) {
                // Handled by NuveiCashierHelper, no need to do anything else, cancel the URL loading
                decisionHandler(.cancel)
            } else {
                // Not handled by NuveiCashierHelper, add your logic and/or complete the loading of the URL
                decisionHandler(.allow)
            }
        } catch {
            debugPrint(#function, "error = \(error)")
            decisionHandler(.allow)
        }
    }
}