Reproduces https://bugs.openjdk.java.net/browse/JDK-8164446 JavaFX's addListener() isn't thread safe.

JDK8164446.java

import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.stage.Stage;

public class JDK8164446 extends Application {

  @Override
  public void start(Stage primaryStage) {
    StringProperty stringProperty = new SimpleStringProperty();

    new Thread(() -> {
      while (true) {
        stringProperty.addListener((observable, oldValue, newValue) -> noop());
      }
    }).start();

    while (true) {
      stringProperty.addListener((observable, oldValue, newValue) -> noop());
    }
  }

  private static void noop() {

  }

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