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# setZoomFactor(_:for:completionHandler:)

Called to set the zoom factor of the tab.

```
optional func setZoomFactor(_ zoomFactor: Double, for context: WKWebExtensionContext, completionHandler: @escaping ((any Error)?) -> Void)
```

## Parameters

`zoomFactor`

The desired zoom factor for the tab.

`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

Sets [`pageZoom`](/documentation/WebKit/WKWebView/pageZoom) of the tab’s web view if not implemented.

## See Also

[`zoomFactor(for:)`](/documentation/WebKit/WKWebExtensionTab/zoomFactor(for:))

Called when the zoom factor of the tab is needed.


---

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