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Will assigning a user to a task/issue give them access to the project as well?

Resolution

During the upgrade process, admins can grant users assigned to a work item permission to a project. 

Furthermore, in task/issue preferences, admins can define default permissions for when a user is assigned to a task or issue, granting them automatic access to the project.  

The project owner can still share the object with users and modify any default permission settings. However, using these settings save the project owner time by presetting permission for project team members.