Once a notebook has been published, you and other workspace members are able to comment on it in real time. Comments can be added to:
SQL and drag/drop cells that have not been hidden
Individual lines of a text block
Images and videos
You are able to comment on a notebook if
The notebook has been published and you are viewing the latest version
The 'View code' toggle is switched off
You are authorised to view the notebook, and are at least a guest of the notebook workspace
You are viewing the notebook on a device with a large enough display
To add a comment, hover over any part of the notebook element and the comment icon will appear on the right. If that notebook element has existing unresolved comments, the comment icon will always be visible.
Comments are grouped into Conversations, and when a new conversation is created it is initially open, and appears under the 'Open' tab. Conversations can be resolved by clicking the 'Resolve' button, and resolved conversations appear under the 'Resolved' tab. Resolved conversations can be re-opened manually, and are automatically re-opened if a new comment is added to them.
When writing a comment, you are able to mention any member of the workspace by typing the @ key - a searchable autocomplete list will appear. Press the Tab or Enter keys, or click a member to add a mention to your comment.
When you submit your comment, the following users will be sent an email:
The creator of the notebook
Anyone who has contributed a version of the notebook
Anyone who has commented in the current conversation
Anyone that is mentioned in your comment
Comments are independent of notebook contents, so if a cell (for example) is deleted, any comments on that cell are retained, though are not visible. If the cell is recreated when restoring an older notebook version, the comments will become visible again.