In groups management page, clicking on the members tab shows all members of the group. Same for messages, it shows the messages exchange within the group. But clicking on activity shows the activity not just for the selected group, but all my activities even those unrelated to the group. E.g., for categories that aren’t private to the selected group. That is confusing. Is it the expected behavior?
It is expected, it’s meant to be the activity of all the group members. So for example, if I wanted to see what the design team is up to on the site I can quickly check Design team - Discourse Meta