(Applies to: all versions of FusionBB)
When viewing a list of topics, you will notice an image in the left column. If this image is "lit up" it means there are new posts in this topic. Check the Icon Legend at the bottom of the screen for a detail of each image used, as different skins can use different images.
Clicking on the subject of the post will take you to the first post in that topic.
Clicking the arrow image right before the subject of the post will take you to the FIRST UNREAD post.
This can be controlled in the user control panel, under Display Settings. Under that header, there is a Auto Jump to New Posts checkbox option. If this is checked and a topic has new posts, then it auto-jumps to the first unread post. If unchecked, you must click the jump arrow (next to the topic title)- elsewise, you will start at the first post of the thread.
In FusionBB versions 2.0 and newer , if the Auto Jump.. is enabled, you can click on the topic title of the post and it will auto-jump to the first unread post. If unchecked, you will start at the first post of the thread (as in version 1.0).