BuddyPress.org

This is a rather detailed question..I’ll post it to the Buddypress forums as well.
I hope somebody can steer me into the right direction…

I am using the buddypress groups on my site. I have used the Buddypress extension API to add an additional menu/page to each group (made as a plugin).
Within that page I am linking via URL and Callback to an external service giving me additional functionality.

This works really well for public groups and hidden groups.
But groups set to private react differently. As soon as I hit the external link Buddypress logs me out.

So…is there a fundamental difference in how Buddypress handles public/private/hidden groups?

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