Firefox browser doesn't switch back to main window after opening new tab

Question

FirefoxDriver doesn't switch back to main window after opening new tab.. This works perfectly fine on ChromeDriver..

I've a main webpage with multiple <a> elements/links and I want to open each link in a new tab and then switch back to main page.

FirefoxDriver is not treating the new tab as a windowHandle.. when I try to print the size of window handles it is returning just one in FirefoxDriver whereas it's returning two in ChromeDriverwhich is fine..

driver.get(url);
WebElement webelement= driver.findElement(By.xpath("html/body/div[1]"));
List<WebElement> allLinks = webelement.findElements(By.tagName("a"));

int totalSize = listofSites.size();


int splitedvalue = totalSize / Integer.parseInt(split2);
int startValue = splitedvalue * (Integer.parseInt(split1) - 1);

        for( int i= startValue ; i<endValue; i++  ){

            links_URL.add(allLinks.get(i).getAttribute("href"));
            String url = allLinks.get(i).getAttribute("href");

            String selectLinkOpeninNewTab = Keys.chord(Keys.CONTROL,Keys.RETURN); 
            allLinks.get(i).sendKeys(selectLinkOpeninNewTab);   

            tabs2 = new ArrayList<String> (driver.getWindowHandles());
                driver.switchTo().window(winHandleBefore);


            }

        for( int k= 1 ; k< tabs2.size(); k++  ){
            System.out.println("size of tab2 "+tabs2.size());

            for(String winHandle : driver.getWindowHandles()){
             driver.switchTo().window(tabs2.get(k));

            }
            routeToproperloginpage(emailID, password, url_array.get(k-1) );   
            driver.switchTo().window(winHandleBefore);
        }

    }