In your inbox, on the top right of each message should show a gray checkmark. Clicking it will turn it green and mark the message as read. If you show all messages (from the three dot menu), you can mark individual messages as unread and then test it out to see how it works marking ones off one by one.
Unfortunately I don’t know how to have the message automatically marked as read if you click on it, and get to the threaded conversation, seems you have to mark as read from the inbox.
In your inbox, on the top right of each message should show a gray checkmark. Clicking it will turn it green and mark the message as read. If you show all messages (from the three dot menu), you can mark individual messages as unread and then test it out to see how it works marking ones off one by one.
Unfortunately I don’t know how to have the message automatically marked as read if you click on it, and get to the threaded conversation, seems you have to mark as read from the inbox.