How to make Mnemonic work with editable Spinner?

Question

Mnemonic mode does not change on e. g. ALT pressed when an editable Spinner is focused. How to fix it? Thank you.

Minimal, Reproducible Example:

package org.example;

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.Spinner;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class EditableSpinnerMnemonicTestApp extends Application {

    @Override
    public void start(Stage stage) {

        Spinner<Integer>
                spinner = new Spinner<>(0, 0, 0),
                editableSpinner = new Spinner<>(0, 0, 0);

        spinner.setEditable(false); // (default) Mnemonic mode changes when focused and ALT pressed
        editableSpinner.setEditable(true); // Nothing happens when focused and ALT pressed

        Label label = new Label("_Test");
        label.setMnemonicParsing(true);
        label.setLabelFor(spinner);
        label.setPadding(new Insets(0,0,3,0));

        stage.setScene(new Scene(new VBox(label, spinner, editableSpinner)));
        stage.show();
    }

    public static void main(String[] args) {
        launch();
    }
}