When looking over citations within the document reviewer, you now have the ability to view and add comments on existing Facts. Click on the highlighted text to open the Fact form. Scroll to the bottom of the form to access the comments thread (below the Source Text field).
To add a comment to a Fact via the citation window, enter your text in the "Write a new comment" field and click the "Save" button directly below the comment box.
Note: Comment thread updates are saved separately from changes to the Fact itself. The "Save" button beneath the comment field is activated when a new comment is typed, indicating a save is needed. Any changes to the Fact itself should be saved using the primary "Save" button.