The rectangle enclosing the insertion point drawn in the extra line fragment rectangle.
- iOS 7.0+
- macOS 10.0+
- tvOS 9.0+
The rectangle is defined in the coordinate system of its
NSZero if there is no extra line fragment rectangle.
The extra line fragment used rectangle is twice as wide (or tall) as the text container’s line fragment padding, with the insertion point itself in the middle.