Roofotp has a default optimized order of appearance for conversations. You can change that by playing with the arrows at the top of every column.
- Notifcations - If you're being notified in a conversation, it'll appear on top
- Oldest conversations - Older conversations will appear on top so they can be prioritized
- Unread + action needed - Conversations that you haven't opened and that require action
- Action needed - Conversations you've opened but haven't acted on yet