I had a long list of favorite questions. I un-marked many of them. A few of the questions still show up in the "favorites" list. Why? Am I doing something wrong? Is it a bug? or a feature...?
I haven't done anything fancy, I simply opened the questions pages and toggled (off) the favorite mark.
Edit: Examples may be
Why does cold metal seem colder than cold air? (physics.stackexchange.com)
Why isn't the 3 body problem solvable? (math.stackexchange.com)
Edit2: the questions have been un-marked long time ago (say months)
Edit3: (after @rene's comment)
They are listed at the global(?) favorites page: https://stackexchange.com/users/1822217/rolazaro-azeveires?tab=favorites
They indeed are not listed at each sites favorites' ages (as linked by rene) I never use those, so I haven't noticed it.