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# styleMask

Flags that describe the window’s current style, such as if it’s resizable or in full-screen mode.

```
var styleMask: NSWindow.StyleMask { get set }
```

## Discussion

The [`styleMask`](/documentation/AppKit/NSWindow/styleMask-swift.property) is settable on macOS 10.6 and later. Setting this property has the same restrictions as the `styleMask` parameter of [`init(contentRect:styleMask:backing:defer:)`](/documentation/AppKit/NSWindow/init(contentRect:styleMask:backing:defer:)). Changing the style mask may cause the view hierarchy to be rebuilt.

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