Description (Required on creation; please attach any relevant screenshots, stacktraces, log files, etc. to the ticket):
I assign a task to the username "" (empty String) via API. The task in the tasklist shows up as "unassigned" because I have the option to click "Claim task". If I click "Claim task" there is an error message "Task '68d43e94-187a-11ed-bfb3-f40270f6362c' is already claimed by someone else." There is no option to reassign the task in the tasklist.
- Update task via API, set username to "".
- Open Tasklist and "Claim task".
There is an error message. I cant unassign or reassign the task.
The task in the tasklist should show as assigned.
Handling of empty string for field "assignee" is handled improperly.
Dont allow "" as valid username.
Treat "" as a valid username in tasklist.
When filtering the tasks by "assigned" (true/false) via REST API the task with assignee "" is interpreted as assigned.