Conversations that have been opened and read can be marked as unread. This is a great visual cue to remind you to check back in to that conversation later or take action on a comment within the discussion.
When you hover over the conversation name, a gray bubble will appear at the end. If you click the gray bubble, it will mark that conversation unread. The gray bubble will become the orange unread notifier and the Kona logo in the upper left will increment.
Note: This feature is time-sensitive so if you do not see the gray bubble it is likely that you refreshed your browser since reading the conversation or it's been too long since you read it.