Azure DevOps: some changes are silently hidden during code review

Do you expect your code review to show all changes, or is it ok if some are silently hidden?

Azure Devops will silently hide some of the edits, and the feedback I got was that this "is not a bug". I don't think it is reasonable to expect devs to pull changes and do their own diff. My feeling is that the main advantage of a PR is viewing those changes.