title: What is the difference between Firefox instance opened by Selenium WebDriver and the browser instance opened manually?
body: <p>I am automating an web application using Selenium WebDriver. This application is supposed to run on both ipad and desktop browser. While testing the automation scripts I found a strange behavior where, selecting a option from a drop-down list causes the page element to hide under floating menu. However this behavior is not seen on browser opened by running firefox.exe manually. The same behavior is seen in Internet Explorer 11 launched by selenium. </p>
  
  <p>I had searched through internet for the possible causes but did not get any relevant justification for this behavior.</p>