ADDITIONAL SYSTEM INFORMATION :
Arch Linux with Oracle JDK package https://aur.archlinux.org/packages/jdk/

A DESCRIPTION OF THE PROBLEM :
Selecting textfield text using the selection methods such as selectPositionCaret, selectEnd, and selectAll doesn't update the selection shown in the control.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Create sample JavaFX project using provided source code, run it, and type a few characters into the text field after the existing text.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
When a character is typed into textfield after existing text, expect to see anchor move to before first character of TextField and blue selection indicator move over letters "Se".
ACTUAL -
As characters are typed into textfield, no selection is shown and the caret stays after the last character typed. The println output shows the caret/anchor and selected text as expected, though:

caret 2
anchor 0
selected text So

---------- BEGIN SOURCE ----------
<?import javafx.geometry.Insets?>
<?import javafx.scene.layout.GridPane?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.TextField?>
<GridPane fx:controller="sample.Controller"
          xmlns:fx="http://javafx.com/fxml" alignment="center" hgap="10" vgap="10">
    <TextField fx:id="textField"/>
</GridPane>

package sample;

import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.TextField;

import java.awt.*;
import java.net.URL;
import java.util.ResourceBundle;

public class Controller implements Initializable {
    @FXML
    private TextField textField;

    @Override
    public void initialize(URL location, ResourceBundle resourceBundle) {
        textField.setText("Some Text");

        textField.textProperty().addListener((observableValue, aBoolean, t1) -> {
            textField.positionCaret(0);
            textField.selectPositionCaret(2);
            System.out.println("caret " + textField.getCaretPosition());
            System.out.println("anchor " + textField.getAnchor());
            System.out.println("selected text " + textField.getSelectedText());
        });
    }
}
package sample;

import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.TextField;

import java.awt.*;
import java.net.URL;
import java.util.ResourceBundle;

public class Controller implements Initializable {
    @FXML
    private TextField textField;

    @Override
    public void initialize(URL location, ResourceBundle resourceBundle) {
        textField.setText("Some Text");

        textField.textProperty().addListener((observableValue, aBoolean, t1) -> {
            textField.positionCaret(0);
            textField.selectPositionCaret(2);
            System.out.println("caret " + textField.getCaretPosition());
            System.out.println("anchor " + textField.getAnchor());
            System.out.println("selected text " + textField.getSelectedText());
        });
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
No workaround identified

FREQUENCY : always