The Cases UI uses the includeComments query parameter, which is deprecated. In 9.0, the query parameter will be removed. We need to update the Cases UI to use the GET /api/cases/{case_id}/comments/_find endpoint to get the comments of the case. By using the includeComments query parameter, all comments were returned with the Case. This can lead to performance issues if the case has a lot of comments. Given that we do not render all comments at once and there is pagination in place, we should apply a similar fetching strategy as we did with the user actions.