I have re written the topic preview mod from scratch. You can now once again preview the first post in a topic by hovering over the topic title with your mouse. This works when browsing forums (viewforum.php) or searching unread/new posts (search.php).
EDIT: You can also preview topics on mobile if you long press the topic title.
![Image](https://i.gyazo.com/9fb6fa5da251cb950cea332900243541.gif)