Apparently the list of offending sites is hardcoded in the extension ( https://github.com/klinskyc/PTOAlert/blob/master/sites.json https://github.com/klinskyc/P

Apparently the list of offending sites is hardcoded in the extension ( https://github.com/klinskyc/PTOAlert/blob/master/sites.json https://github.com/klinskyc/PTOAlert/blob/master/sites.json ) and the extension is not updated to reflect changes on the sites.