To reproduce using the MonkeyTester and an OS configured with RTL input:

- switch to the TextArea page
- change the node orientation to RTL (Window -> Orientation RTL)
- switch to RTL language input (Hebrew for example)
- type in some RTL text, then 123.  Notice there is no split caret.
- mouse click on where the caret is (leading edge of the leftmost digit)
- notice there is no split caret, and the caret did not move
- type some more RTL text

Expected: the text is expected to be inserted to the left of the digits.
Observed: the text is inserted to the right of the digits where no caret was present.


```
public class TextArea_RTL_8318840 extends Application {
    @Override
    public void start(Stage stage) throws Exception {
        TextArea textArea = new TextArea();

        Scene scene = new Scene(textArea);
        scene.setNodeOrientation(NodeOrientation.RIGHT_TO_LEFT);

        stage.setScene(scene);
        stage.setTitle("TextArea in RTL Mode");
        stage.show();
    }
}
```