Hello Elena,
thank you for your answer. Turns out I was looking in the wrong place, so I got a bit further now, but I'm not there yet.
I got so far that I have created a Subscription center and added it to my portal's menu, which is good. But I was looking more for a way to augment the profile page with just a list of checkboxes for all newsletters we have so they can just check the boxes of the information they want to receive.
This way would also work, I suppose, but would require the user to go to a wholly different page, that I would also need to maintain. Or am I missing something?
Thanks for your help so far.
