def include_in_user_agent(name, suffix = nil)
      return if name.nil?
      unless @config.read('library.include_utilities_in_user_agent') == false
        @extra_user_agents_lock.synchronize do
          @extra_user_agents[name] = suffix
        end
      end
    end
def include_in_user_agent(name, suffix = nil)
      return if name.nil?
      unless @config.read('library.include_utilities_in_user_agent') == false
        @extra_user_agents_lock.synchronize do
          @extra_user_agents[name] = suffix
        end
      end
    end
Adds a custom string to the user agent, one time, the next time a user
 agent is generated. This will be rendered in the format "name/suffix",
 or just "name" if the suffix is nil or omitted.