Conversations aren't marked as read when they are opened from a notification.
- Long press on a conversation and press "Mark as unread" to reveal a notification.
- Press the home button to put HSMS in the background.
- Pull down on the notification to open the notification drawer.
- Tap on the body of the notification (not the buttons).
- Tap on the back button to reveal the conversation list.
The conversation is marked as read.
The conversation isn't marked as read.