This problem was reported upstream last November: https://secure.phabricator.com/T6516
The import of Phabricator upstream into Differential created comments and status changes to tasks in Wikimedia Phabricator because upstream task numbers match local task numbers.
Only affects 4-digit-or-less tasks.
We have already manually reverted all status changes (performed by "Diffusion" or "epriestley", I did not spot any other accounts existing both here and in upstream by going through https://phabricator.wikimedia.org/feed/query/projects/ ), but the
Unknown Object (Commit)
part is ugly and confusing and should be reverted if possible.