Collapses comment trees on Hacker News. To collapse a comment, click on the [-] button at the right of the commet header. Changes in 1.2.1: * Fixed a bug regarding HN Collapse not working properly when the black line of mourning is visible on on HN. * Fixed a bug regarding the positioning of the collapse button on deleted comments. Changes in 1.2: * Added support for HTTPS. Changes in 1.1: * Fixed bug regarding not hiding the "reply" link when the comment has no children. * Added support for the "threads" page.