Once you’ve submitted your comment, that comment will appear in the Comments pane at the right-hand side.
Note: Not all files have the comment feature. For example, you can’t comment on an mp4 or PDF file.
You can also choose to reply to a comment by pressing Reply underneath an existing comment. This opens a new comment thread, with the original comment at the top of the right pane and any other comments appearing beneath it. To return to the other comments, simply select Back to all comments at the top of the pane.
To exit commenting, select the Exit comment chat bubble icon in the top right-hand side of the screen.