Before revision: Such a person may spend inordinate amounts of time on unpopular, little known, or non-mainstream activities, which are generally either highly technical, abstract, or relating to niche topics such as science fiction or fantasy, to the exclusion of more mainstream activities.
After revision: Such a person may spend inordinate amounts of time on unpopular, little known, or non-mainstream activities, which are generally either highly technical, abstract, or relating to niche topics such as science fiction , fantasy, and editing Wikipedia to the exclusion of more mainstream activities.