@TP-Link Sorry I do not remember the previous firmware. Below will be some sites that I am having issues visiting. 

https://baike.baidu.com/   ---- like Wikipedia thing but from Baidu. The search engine (https://www.baidu.com/) is working. 

https://www.arknights.global/ ----I am also having issues with this game. the site is able to open but I can not connect to the game server. 

https://xl11.xunlei.com/ ------- the site of software that's for downloading (command test shows time out)

https://www.wps.cn/ ------ office suite software.

http://mumu.163.com/ ------ Android simulator for desktop. 

Basically, all the sites are timing out when pinging from command. 

@TP-Link 

I do not think other brands' routers will have the issue since if I have Ethernet cable directly from the modem, the sites are all able to open. But I need the mesh network in my place. 

I have not set up any parental control or firewall rules and even QoS. 

And, yes, before the firmware upgrade, the sites are all able to access

All devices have the same issue if connected to Deco.

Here is the information about my ISP 

CIK Telecom

104.152.162.104