For example: https://secure.phabricator.com/tag/wikimedia/
```
>>> UNRECOVERABLE FATAL ERROR <<<
Call to a member function getBuiltinKey() on a non-object
/core/lib/phabricator/src/applications/project/controller/PhabricatorProjectViewController.php:23
┻━┻ ︵ ¯\_(ツ)_/¯ ︵ ┻━┻
```
The project works just fine if you visit https://secure.phabricator.com/project/manage/404/