code: public void addConvergedSessionDeletegateToSession(SessionConfig sessionCookieConfig, HttpServerExchange serverExchange, ConvergedSessionDelegate convergedSessionDelegate){
          String sessionId = sessionCookieConfig.findSessionId(serverExchange);
          ConvergedInMemorySession sess = sessions.get(sessionId);
          if(sess!=null){
              sess.addConvergedSessionDelegate(convergedSessionDelegate);
          }
  
      }
docs: FIXME:kakonyii. sessionManager.createSession() is also called from  io.undertow.util.Sessions.getOrCreateSession(), so this method should be called from there also