### Handle URL Authentication Challenges

Source: https://github.com/yashigani/webkitplus/blob/master/README.md

Implement the webView(_:didReceive:completionHandler:) method in your WKNavigationDelegate to handle URL authentication challenges. Use UIAlertController(for:completion:) to present an interface for user input.

```swift
/// in `WKNavigationDelegate` object
func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
    guard let alert = UIAlertController(for: challenge, completion: completionHandler) else {
        // Should call `completionHandler` if `alertForAuthentication` return `.None`.
        completionHandler(.performDefaultHandling, nil)
        return
    }
    present(alert, animated: true, completion: nil)
}
```

--------------------------------

### Implement WKUIDelegate for Presenting Alerts

Source: https://github.com/yashigani/webkitplus/blob/master/README.md

Use WKUIDelegatePlus to provide standard implementations for presenting alerts from JavaScript within your WKWebView. Assign an instance of WKUIDelegatePlus to your webView's UIDelegate property.

```swift
override public func viewDidLoad() {
    super.viewDidLoad()
    UIDelegate = WKUIDelegatePlus(self)
    webView.UIDelegate = UIDelegate
}
```

--------------------------------

### Observe WKWebView Property Changes with WebViewObserver

Source: https://github.com/yashigani/webkitplus/blob/master/README.md

Utilize WebViewObserver to observe changes in WKWebView properties like title and progress using closures, avoiding the complexities of traditional KVO. Initialize the observer with your WKWebView instance.

```swift
lazy var observer: WebViewObserver = WebViewObserver(self.webView)
override public func viewDidLoad() {
    super.viewDidLoad()
    observer.onTitleChanged = { [weak self] in self?.title = $0 }
    observer.onProgressChanged = { [weak self] in self?.progressbar.progress = $0 }
}
```

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