This below fails to navigate the second time, why?
Is there a bug in UI4J or something in my code/system? On Ubuntu 15.10. Using Java 8u40.
package mypackage.Web.tests.main;
import com.ui4j.api.browser.BrowserEngine;
import com.ui4j.api.browser.BrowserFactory;
import com.ui4j.api.browser.Page;
public class UI4JNavigateShowHideErrorDemo {
    public static void main(String[] args) throws InterruptedException {
        BrowserEngine engine = BrowserFactory.getWebKit();
        navigateShowAndClose(engine);
        navigateShowAndClose(engine);
        System.out.println("Never reaches this stage because on the second navigate it gets stuck.");
    }
    public static void navigateShowAndClose(BrowserEngine engine) throws InterruptedException {
        System.out.println("Navigating");
        Page page = engine.navigate("http://www.google.com/");
        System.out.println("Showing");
        page.show();
        System.out.println("Sleeping");
        Thread.sleep(500);
        System.out.println("Closing");
        page.close();   // Same with page.hide()
    }       
}
