Now you can take screenshots of elements in your environment and post them as a comment on the corresponding pull request.
Click the new "Select element" button in the bottom-left corner of an environment. Then select any element on the page. A modal dialog will appear, where you can add a text comment to supplement your attached screenshot.
Furthermore, your browser metadata automatically gets included in the comment. Developers: no more following up with reviewers to see what browser they were using!