The part of the URL that you want to remove is the context path of your application. PrettyFaces cannot change the context path because it is assigned for application by the container.
But you can easily configure some other context path for your application. But how to do this depends on the container you are using. In case of Apache Tomcat for example you just have to name the WAR file you are deploying ROOT.war.
What container do you use?
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