9.8 Using secondary windows in HTML Help
When you jump to a secondary window in HTML Help, you get only one instance of that window. Whenever you target the secondary window, the window itself stays in place, and only the content is replaced.
§9.8.1 Defining secondary windows for HTML Help
§9.8.2 Jumping from a topic to a secondary window
§9.8.3 Jumping from contents or index to a secondary window
§7.7 Jumping to secondary windows in Help systems
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