code: public ExtWebDriver getNewSession(String key, String value, boolean setAsCurrent)
              throws Exception {
  
          /**
           * This is where the clientPropertiesFile is parsed and key-value pairs
           * are added into the options map
           */
          Map<String, String> options = sessionFactory.get().createDefaultOptions();
          options.put(key, value);
  
          return getNewSessionDo(options, setAsCurrent);
      }
docs: Create and return a new ExtWebDriver instance. The instance is
  constructed with default options, with the provided key/value pair
  overriding the corresponding key and value in the options. This is a
  convenience method for use when only a single option needs to be
  overridden. If overriding multiple options, you must use
  getNewSession(string-string Map, boolean) instead.
  
  @param key
  The key whose default value will be overridden
  @param value
  The value to be associated with the provided key
  @param setAsCurrent
  set to true if the new session should become the current
  session for this SessionManager
  @return A new ExtWebDriver instance
  @throws Exception