The color to use when painting the autocorrection Rect.
For CupertinoTextFields, the value is set to the ambient CupertinoThemeData.primaryColor with 20% opacity. For TextFields, the value is null on non-iOS platforms and the same color used in CupertinoTextField on iOS.
Currently the autocorrection Rect only appears on iOS.
Defaults to null, which disables autocorrection Rect painting.
final Color autocorrectionTextRectColor