Some users not found when not logged in

1. Open bugreports.qt.io but don't log in.
2. Select "Issues" -> "Search for Issues" from the menu.
3. Click on "Assignee: All".
4. Type "vivek".
   User vivek will be found.
5. Clear that edit and type "rlohning" instead.
   rlohning will not be found.

This seems wrong. If users should not be found before logging in, no user should be found. If users should be found, all users should be found.