ADDITIONAL SYSTEM INFORMATION :
It works in JavaFX 8. I did not try other JavaFX releases such as 9-15.

A DESCRIPTION OF THE PROBLEM :
It relates to dialogs where the contentText usually nicely wraps to the next line if it does not fit.

The issue appears for cases when setting "glass.win.uiScale" to "1.5". (maybe other scales also)

REGRESSION : Last worked in version 11

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Open JavaFX dialog with longer contentText string.
Set scale to 1.5
System.setProperty("glass.win.uiScale", "1.5");

# Code to reproduce

see provided code



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
See https://github.com/danielpeintner/Java11Test/issues/5

There you can find two images. The first one shows the expected result (contentText nicely wrapped).
ACTUAL -
See https://github.com/danielpeintner/Java11Test/issues/5

There you can find two images. The second one shows the failures (contentText *not* nicely wrapped).

---------- BEGIN SOURCE ----------

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class TestDialog extends Application {
    public static void main(String[] args) {
        System.setProperty("glass.win.uiScale", "1.5");
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("DialogTest!");
        Button btn = new Button();
        btn.setText("Show Dialog");
        btn.setOnAction(event -> {
            Alert dialog = new Alert(Alert.AlertType.CONFIRMATION);
            dialog.setTitle("MyTitle");
            dialog.setHeaderText("MyHeader");
            dialog.setContentText("myContent 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30");
            // dialog.getDialogPane().setExpanded(true); // makes the 2nd text line appear but moves the buttons out of the scene
            dialog.showAndWait();
        });
        BorderPane bp = new BorderPane();
        bp.setCenter(btn);
        primaryStage.setScene(new Scene(bp, 300, 250));
        primaryStage.show();
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Setting dialog.getDialogPane().setExpanded(true); makes the line appear but the dialog buttons move out of scene.

FREQUENCY : always