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# setWindowState(_:for:completionHandler:)

Called to set the state of the window.

```
optional func setWindowState(_ state: WKWebExtension.WindowState, for context: WKWebExtensionContext, completionHandler: @escaping ((any Error)?) -> Void)
```

## Parameters

`state`

The new state of the window.

`context`

The context in which the web extension is running.

`completionHandler`

A block that must be called upon completion. It takes a single error argument, which should be provided if any errors occurred.

## Discussion

The implementation of [`windowState(for:)`](/documentation/WebKit/WKWebExtensionWindow/windowState(for:)) is a prerequisite.

Without it, this method will not be called.

## See Also

[`windowState(for:)`](/documentation/WebKit/WKWebExtensionWindow/windowState(for:))

Called when the state of the window is needed.


---

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