User other than team developer can't see project issues

I need to grant user observer permissions on a project.
Specifically, to view project issues, comments and attachments.
No editing.

Here's the list of things I've tried that didn't help me out:
- Add global observer role to user;
- Add observer role on a project to user;
- Create and assign to user team role for a project with required (as it seemed to me) permissions;
- Create and assign to user team role for a project with all exactly the same permissions that developer role have.

The only thing that makes issues of a required project visible to user is to add user to project team, which grants him a developer team role on that project which is exactly what I do not want to do.