I wondered about this. I would sincerely hope that the permissions list is already priority-sorted somehow; otherwise, it’d be trivial to just list five innocuous permissions first and then put the dangerous ones later. Even with scrollbars, most users would just see the first few and likely not bother to scroll down at all. Note that in the author’s post, one of the dangerous permissions (read and modify data for all websites) is already listed in the box.