In order for a secondary window to be used, you must assign it to a style as follows:
1. On the Icon bar, click Project.
2. Select the Paragraph Styles or Character Styles item from the left pane.
3. In the right pane, select the name of the style to be edited.
Note that the property pane changes to show the properties of the selected style.
4. In the property pane, set the Window property to the window type you would like to be assigned to this style.
You can assign one window to multiple styles. You can also assign the main window to one or more styles to prevent the associated topics from being displayed in a secondary window.