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# indexInWindow(for:)

Called when the index of the tab in the window is needed.

```
optional func indexInWindow(for context: WKWebExtensionContext) -> Int
```

## Parameters

`context`

The context in which the web extension is running.

## Discussion

This method should be implemented for better performance. Defaults to the window’s
[`tabs(for:)`](/documentation/WebKit/WKWebExtensionWindow/tabs(for:)) method to find the index if not implemented.

---

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