If you were also stuck with Firefox 47 and Selenium 2.53 issue then this is right time to start experimenting with Marionette. But Before delving into Marionette, let’s see what a web browser engine is. Web browser engine is a program which renders markup content (i.e. html, xml, images etc) and the format information (i.e. css, xsl etc). It is also known as layout or rendering engine. In simple words, web browser engine is responsible for how you are able to see a web page in a browser, email client or e-book reader. Some of the most popular web browser engines are - Webkit which is used in safari and chrome browsers Gecko used in Firefox, Thunderbird email client Marionette is WebDriver version for Mozilla’s Gecko engine. It can control both the browser (menu, function etc) also known as chrome (don’t confuse with google chrome browser ;-)) and the content within the browser (something which is of immense value for test automation). Marionette also follow...