It's a filter for the Stack Overflow API, you can test it out: * https://api.stackexchange.com/2.2/questions/16476924?order=desc&sort=activity&site=stackoverfl

It's a filter for the Stack Overflow API, you can test it out: * https://api.stackexchange.com/2.2/questions/16476924?order=desc&sort=activity&site=stackoverflow https://api.stackexchange.com/2.2/questions/16476924?order=d... * https://api.stackexchange.com/2.2/questions/16476924?order=desc&sort=activity&site=stackoverflow&filter=!9YdnSJ*_T https://api.stackexchange.com/2.2/questions/16476924?order=d... I think this should contain a list of what's in the filter: https://api.stackexchange.com/2.3/filters/!-*f(6s6U8Q9b https://api.stackexchange.com/2.3/filters/!-*f(6s6U8Q9b