Auto refresh assignee of MR/issue when it is updated by another user

Currently, if a user has MR/issue opened in a browser, assignee of this MR/issue will not be auto-updated for this user if another user changes it.

Let's say one of GitLab users is working on a merge request or issue:

another user (reviewer) had made several discussions and assigned it back to the user to address them
the MR page was updated with discussions, but not with the assignee of the MR, creating a partly stale and misleading presentation of status
This generated misunderstanding about who was currently responsible and prevented reassigning the MR as needed to follow the workflow
This nearly caused a deadline to be missed

If the assignee of MR/issue is changed, the page should be auto-updated with this new data.

Another user who has the page with issue / MR opened will see that the assignee has been changed.