Currently, it can only show the diff for edits, but not if a new page is created (e.g. talk page), which might be a bit confusing.
@Sitic: I am resetting the assignee of this task because there has not been progress lately (please correct me if I am wrong!). Resetting the assignee avoids the impression that somebody is already working on this task. It also allows others to potentially work towards fixing this task. Please claim this task again when you plan to work on it (via Add Action... → Assign / Claim in the dropdown menu) - it would be welcome! Thanks for your understanding.