One notification per conversation

A conversation has one notification at any moment, and not one per line.

If the other side wrote five messages in one conversation and you have not opened it yet, you see one notification. It moves to the latest message instead of being joined by another.

Once you have read the conversation, that notification closes. If the other side writes again later, a new one opens.

The notification shows the writer's name and the start of the message. Tapping it opens the conversation.