pop-ups to update entering chatters: mandatory creator-controlled popups that require click to dismiss. creator can enable/disable.
There are often breaking/emerging situations where creators want everyone who enters the chat to be aware of some key recent information. I know one existing option for this is that creators can pin a message above chat. However, those pinned comments are often not very visible. One possible way to more reliably grab chatter attention is to to give those pinned comments a different, contrasting background color. However, I think a better way to insure that all people entering chat sees any crucial, new info, is if the streamer can enter into the system a "mandatory to read message" upon entering that they have to click to dismiss (like they have to do when agreeing to chat rules before the first chat). This would save creators a lot of frustration as they often feel like they have to constantly repeat themselves as new chatters are constantly entering.