Improve UI feedback when Duo has started reviewing / is interacting
Problem to Solve
Currently when a review is requested of Duo an initial comment is posted that says it will perform the review. However, it's not clear to users that anything is happening.
Proposal
We display commenting/bouncing dots and a message to show that GitLab Duo is generating the review or replying to a comment.
This allows us to use a similar pattern across GitLab Duo Code Review and GitLab Duo Chat.
We will display this commenting state in the following areas:
- Activity feed
- Reviewers in the sidebar
- In thread replies
Activity feed
This UI element provides feedback eventually replaces the initial comment that is used as a placeholder today
Text: GitLab Duo is reviewing your merge request and will let you know when it’s finished.
| Current | Proposal |
|---|---|
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Reviewer sidebar
Another thing we will add is to reflect this "active reviewing" state with the commenting/bouncing dots in the reviewer sidebar. The reason we are doing this for GitLab Duo but not other reviewers is that a review from GitLab Duo comes back in seconds versus reviewers that could take hours to days so it will remaining using the 
icon.
Updated review started icon for GitLab Duo Code... (!189038 - merged)
In thread replies
We allow users to @-mention GitLab Duo in threads to ask follow up questions but today we do not provide any feedback that the question has been received or GitLab Duo is doing anything with it.
We will display the commenting animation and a message that GitLab Duo is working on a reply.
Text: GitLab Duo is working on a reply
