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To create a Task from comments:
Open an Authoritative Document and highlight the area of the Authoritative Document where you want to leave a comment.
Icons that enable you to add comments appear on the upper-right side of the text you selected:
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Click the Add Comment icon.
The Reviews dialog appears:
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To assign your comment to a user, type + followed by the username.
Select the required username from the suggestions that appear.
Select Assign to <username>.
You can also select a due date for the comment if required.
Click Save.
The comment is now displayed in the Tasks view of the landing page.