Phabricator is no longer maintained upstream. See https://admin.phacility.com/phame/post/view/11/phacility_is_winding_down_operations/.
Also see https://secure.phabricator.com.
Effective June 1, 2021: Phabricator is no longer actively maintained.
We should decide whether we want to keep phabricator or move to another bug tracker.