The 'In a new topic pane' invocation option causes the hyperlink target to add a new instance of the topic pane.[The topic pane is the area in your browser that contains a topic: the content, the title and eventually the action bar. If you browse a book or a folder then the topic you select in the folder tree is shown on the right in the topic pane.] It is only applicable to hyperlinks to topics. The advantage of using this option in stead of the option In the folder tree is that the click on the hyperlink never disturbs the selection path in the folder tree.