le pilote opera ne fonctionne pas avec Selenium-Java

J'écris un script de test cross browser en utilisant Selenium web driver - Java. Mes navigateurs Firefox, chrome et IE s'ouvrent et exécutent avec succès le script. Mais, dans opera, seul le navigateur s'ouvre. Même driver.manage().window().maximize(); ne fonctionne pas non plus. Ouvrez simplement le navigateur et restez jusqu'à ce que je le ferme. Lorsque je ferme le navigateur manuellement, la suite de tests échoue.

Voici ma classe java.

package multiBrowser;

import org.testng.annotations.Test;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.firefox.FirefoxProfile;
import org.openqa.selenium.firefox.internal.ProfilesIni;
import org.openqa.selenium.ie.InternetExplorerDriver;
import org.openqa.selenium.opera.OperaDriver;
import org.testng.annotations.Parameters;

public class MultiBrowserClass {

    WebDriver driver;

    @Test
    @Parameters("browser")
    public void multiBrowsers(String browserName) throws InterruptedException{

        if(browserName.equalsIgnoreCase("firefox")){

            System.setProperty("webdriver.firefox.marionette","D:\\My Work\\Setup\\JAR\\geckodriver.exe");
            ProfilesIni profile = new ProfilesIni();    
            FirefoxProfile myprofile = profile.getProfile("default");
            driver = new FirefoxDriver(myprofile);

        }
        if(browserName.equalsIgnoreCase("chrome")){

            System.setProperty("webdriver.chrome.driver", "D:\\My Work\\Setup\\JAR\\driver\\chromedriver.exe");
            driver = new ChromeDriver();
        }
        else if(browserName.equalsIgnoreCase("IE")){

            System.setProperty("webdriver.ie.driver", "D:\\My Work\\Setup\\JAR\\driver\\IEDriverServer.exe");
            driver = new InternetExplorerDriver();
        }
        else if(browserName.equalsIgnoreCase("opera")){

            System.setProperty("webdriver.opera.driver", "D:\\My Work\\Setup\\JAR\\driver\\operadriver.exe");
            driver = new OperaDriver(); 

        }

        driver.manage().window().maximize();

        driver.navigate().to("https://");

        System.out.println(driver.getTitle());

        driver.findElement(By.xpath("//div[@id='navbar-main']/ul/li[5]/a")).click();    
        driver.findElement(By.xpath("//div[@id='navbar-main']/ul/li[5]/ul/li/a")).click();
        Thread.sleep(3000);
        driver.findElement(By.name("email")).clear();
        driver.findElement(By.name("email")).sendKeys("[email protected]");
        driver.findElement(By.name("password")).clear();
        driver.findElement(By.name("password")).sendKeys("1qaz2wsx");
        Thread.sleep(3000);
        driver.findElement(By.xpath("//form[@id='loginform']/div[8]/button")).click();
        Thread.sleep(5000);

        if(driver.getPageSource().contains("Welcome [email protected]")){
            System.out.println("User Successfully logged in");

        }else{
            System.out.println("Username or password you entered is incorrect");
        }

        driver.quit();

    }

}

Voici le testng.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name="Suite">

  <!-- firefox -->  

  <test name="FirefoxTestCases">  
      <parameter name="browser" value="firefox"/>  
      <classes> 
        <class name="multiBrowser.MultiBrowserClass"/> 
      </classes> 
  </test> 


  <!-- chrome -->  

  <test name="ChromeTestCases">  
      <parameter name="browser" value="chrome"/>  
      <classes> 
        <class name="multiBrowser.MultiBrowserClass"/> 
      </classes> 
  </test>


   <!-- internet explorer -->

  <test name="IETestCases">  
      <parameter name="browser" value="IE"/>  
      <classes> 
         <class name="multiBrowser.MultiBrowserClass"/> 
      </classes> 
  </test>

     <!-- Opera -->

  <test name="OperaTestCases">  
      <parameter name="browser" value="opera"/>  
      <classes> 
         <class name="multiBrowser.MultiBrowserClass"/> 
      </classes> 
  </test>

</suite> <!-- Suite -->

J'ai téléchargé operadriver depuis cette page (operadriver_win64.zip).

Voici comment le navigateur Opera s'ouvre.

Opera version est 41.0.2353.56.

Merci d'avance. :)