You yourself said the internet keeps dropping in China.
It's an error. I'm not sure why it'd tell you to refresh, maybe the network connection borked but I'm not sure. The webchat you used is ran by Freenode, thus I have zero control over it.
Depending on how much you care it may be a good idea to install
https://hexchat.github.io/ and configure it to connect to our IRC instead of using a webclient. It should already be set up to configure to freenode as part of the default server list, then all you have to do is /join ##minichan