User cards for anonymous visitors immediately dissappear with "500 Internal Server Error" in `card.json?include_post_count_for`

No I never got that to work. At any rate that would have been disabled in safe mode.

The ?include_post_count_for=xxxxx number is the number of the topic ID, not the user.

I assumed the function that is failing was for the “X posts in this topic” button that appears in a user card.