JIRA Workflow: only allow transition if assignee is not a specific user

[Marc Mast]

I want a validation to restrict a transition (in progress) for any user but a specific user (dashboard user in this case, with username dashboard and fullname Dashboard User).

I tried builing a JQL validation with JIRA Workflow Toolbox, but that doesn't work: if I set the assignee to a valid user it still gives the error. 

Used JQL: 

%{00003} != dashboard

[Joe Pitt · Accepted solution]

I use the jira suite utilities (free) to add a condition to the workflow to restrict by role. It doeen't do individual users. I suggest creating a project role and using it.