https://secure.phabricator.com/w/changelog/2016.05/
The latest build from Phabricator broke the "Sprint" application with the below error:
UNRECOVERABLE FATAL ERROR <<<
Call to undefined method PHUIIconView::setIconFont()
/opt2/apps/phab-externals/sprint/src/controller/board/SprintBoardViewController.php:724
┻━┻ ︵ ¯\_(ツ)_/¯ ︵ ┻━┻
https://secure.phabricator.com/w/changelog/2016.05/
My guess is that the latest change mentioned feature (#2) may have caused the issue:
Users can now choose a user icon.