RoboHelp makes it easy to insert HTML comments in topics.
Inserting an HTML Comment
To insert an HTML comment, open a topic in theĀ Design EditorĀ and place the cursor where you wish to insert the comment. From theĀ HTML sectionĀ of the Insert tab, click on theĀ Text Box dropdown menuĀ and selectĀ Comment.
Type your comment in theĀ Comment EditorĀ in the following format –Ā <!–a comment ->Ā and click OK.