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# sourceTextScaling

The text-scaling mode to associate with the document’s content.

```
static let sourceTextScaling: NSAttributedString.DocumentReadingOptionKey
```

## Discussion

The value of this property is one of the options of the <doc://com.apple.documentation/documentation/UIKit/NSTextScalingType> type. Some platforms scale fonts to improve their appearance. Include this option to specify the text-scaling mode to associate with the document’s contents on disk.

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