There are :
- the Project with 2 boards ( 1- Story, Bug; 2- Task) and 3 standard issue types (Task , Story, Bug)
- 2 groups (employee and freelancers)
Case : "Employee" can see and manage all issues and see all boards. "Freelancers" only Tasks and board #2.
So , when I share board's filter permissions for "Freelancers" group they see board and other issue's types on Dashboard.