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# window(_:willUseFullScreenContentSize:)

Called to allow the delegate to modify the full-screen content size.

```
@MainActor optional func window(_ window: NSWindow, willUseFullScreenContentSize proposedSize: NSSize) -> NSSize
```

## Parameters

`window`

The window to enter to full-screen mode.

`proposedSize`

The proposed window size.

## Return Value

The window size to use when displaying content size.

## Discussion

---

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