When adding a reference qualifier to the Additional Assignee field for a Visual Task Board, it is shown on the form view for a VTB task, however the qualifier does not get honoured on the VTB view itself.
Steps to Reproduce
1. Open the dictionary entry for additional assignee list:
2. Add a reference qualifer (e.g. name does not contain a).
3. Go to vtb_task table and try and add an additional assignee Abel Tuter to a task, notice that the qualifier works fine here and Abel Tuter can't be added (You'll need to add the Additional Assignee field to the form).
4. Go to the Visual Task Board itself and open the same task from there.
5. Try to add Abel Tutor again to the task as an additional assignee.
Observe the reference qualifier is not honoured, so all users are returned in the list including Abel Tuter.
Related Problem: PRB960086