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# allowsFullHeightLayout

A Boolean value that indicates whether full-height sidebars appear in the window after you set a style mask.

```
var allowsFullHeightLayout: Bool { get set }
```

## Discussion

This property only applies to [`NSSplitViewItem.Behavior.sidebar`](/documentation/AppKit/NSSplitViewItem/Behavior-swift.enum/sidebar) and [`NSSplitViewItem.Behavior.inspector`](/documentation/AppKit/NSSplitViewItem/Behavior-swift.enum/inspector). The default value is <doc://com.apple.documentation/documentation/Swift/true>.

---

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