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# webView(_:runJavaScriptAlertPanelWithMessage:initiatedByFrame:completionHandler:)

Displays a JavaScript alert panel.

```
optional func webView(_ webView: WKWebView, runJavaScriptAlertPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: @escaping @MainActor @Sendable () -> Void)
```

## Parameters

`webView`

The web view invoking the delegate method.

`message`

The message to be displayed.

`frame`

Information about the frame whose JavaScript process initiated this call.

`completionHandler`

The completion handler to call after the alert panel has been dismissed.

## Discussion

For user security, implementations of this method should call attention to the fact that a specific website controls the content in this panel. A simple formula for identifying the controlling website is `frame.request.URL.host`. The panel should have a single OK button.

---

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