Version 4 also alters the UI for these areas. For example, fluid view in v4 displays the topic starter at the front, with no avatar for the last poster. We’ve simply carried this design over into v5. Categories and topic lists have different designs because they’re displaying different types of data. Version 5 has many intentional changes to the UI, and certain areas will be different to v4. This is expected as it’s a significant rewrite with a full redesign. The HTML for the last poster avatar has purposely been kept in the source, so if you really want to restore the v4 design, you’re welcome to via Custom CSS 🙂