You can add comments to an issue. You can also reply to comments from other Blue Relay users.
Click Files in the side panel. (If Files is not shown, see Customize the Side Panel for details on how to add it.)
Go to a file with an issue.
Click the down arrow on the far right side of the issue to expand the issue.
Use the comment icon to add a comment.
Comments can be threaded, so you can add a comment to someone else's comment, or to the issue itself.
