The JavaDocs for Stage.resizableProperty() state that the property cannot be bound and attempting to do so will throw a RuntimeException. While Stage.resizableProperty().bind(...) indeed throws a RuntimeException, Stage.resizableProperty().bindBidirectional(...) does not.

If bindBidirectional(...) is safe, the documentation should be clarified to make this clear, as it provides a convenient workaround in many use cases. If it is not safe, which is what I suspect, then it should also throw an Exception.

See forum thread: https://forums.oracle.com/forums/thread.jspa?threadID=2518419&tstart=0

The example from that thread, reproduced here, runs in Lombard but it's not clear if this really should throw a RuntimeException:

import javafx.application.Application;
import javafx.scene.GroupBuilder;
import javafx.scene.Scene;
import javafx.scene.SceneBuilder;
import javafx.scene.control.CheckBox;
import javafx.scene.control.CheckBoxBuilder;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
 
public class BiDiBug extends Application {
  
  CheckBox checkBoxResizable;
 
  public static void main(String[] args) {
    Application.launch(args);
  }
  
  @Override
  public void start(final Stage stage) {
  
  stage.setResizable(true);
    
    Scene scene = SceneBuilder.create()
      .width(200)
      .height(100)
      .fill(Color.TRANSPARENT)
      .root(
        GroupBuilder.create()
             .children(
                checkBoxResizable = CheckBoxBuilder.create()
                  .selected(stage.isResizable())
                  .text("Is Stage resizable")
                  .build()
                
              )
              .build()
          )
       .build();
    
    checkBoxResizable.selectedProperty()
            .bindBidirectional(stage.resizableProperty());

    stage.setScene(scene);
    stage.show();
  }
}