While watching a stream there have been two people just spamming a streamers chat. It’s extremely off putting for both the streamer and the viewer, as such this issue needs to be addressed with high priority to prevent losing streamers or viewers.
Spammers usually will
a) Spam the same message in fast succession.
b) Spam the channel with lots of random messages.
In either case there’s a fast chat output from a single person, which can be easily detected – nobody can write hundreds of characters a second. If such a behavior is detected it’s clearly disruptive person and most likely a spam. This person should be temporarily or permanently banned from the chat.
If one user keeps posting the same message over and over again within a short time frame, which again is easily detectable, then this is clearly a spammer and that person should be completely banned from the chat and probably permanent banned from the website.
If spammers keep making trouble, you should really reconsider your sign up strategy and how you can prevent automated account creations.