I think it should be working on the discussions home page as when I go to the discussions I would want to see my favorites right away - I did not try it on profile but will now. Still it needs to work regardless of where it is placed - do you agree? 😀
I don't know, if I do the same experiment with the same block for "post" the result is the same. It may have been designed to show others what you have done, not yourself. Case to follow :-)