When group conversations have become too busy you can’t keep up with them any longer, or maybe you just want to totally ignore them — at least for the time being, you actually have the option to mute them by going to the group’s Chat Info & Settings, and there’s a toggle to Mute Group.
However, what does this really do totally defeats its purpose. Yes, it stops the notification sounds from going off, and new messages don’t appear in the notification center, but the app badge still shows how many messages you’ve missed from these muted group conversations. Also, when you open the app, the Chats tab still shows the number of unread messages even when they’re from the “muted” ones, which clearly gets in the way when your intention was to totally ignore them.
So, unless and until Viber corrects this issue, I’m turning off notifications for this app altogether. Or, perhaps, uninstall Viber completely.