Merge request view shows old MRs as recently updated

Summary

It appears that if we delete a user from gitlab, all merge requests that this user was involved in are marked as updated at the point in time where we delete the user. Look at my MRs:

image

The ones marked with yellow are very old ones, however, they are marked as "updated a day ago". All of them are related to a "ghost user", which I assume is a deleted user. I'd prefer to have them not marked as updated.

Steps to reproduce

Create a user A, let him participate (e.g., add comment) in merge requests of other user B. Delete user A. Merge request of user B will show as recently updated.

Example Project

What is the current bug behavior?

Merge request shows as updated although it was not updated

What is the expected correct behavior?

It should not show as updated recently.

Relevant logs and/or screenshots

Output of checks

Results of GitLab environment info

Results of GitLab application Check

Possible fixes