They're added as domain-specific if you use the element picker, but they don't have to be. They show up in the extension's control panel. Using the element pic

They're added as domain-specific if you use the element picker, but they don't have to be. They show up in the extension's control panel. Using the element picker to block HN's footer generates a rule like this: ! 7/8/2018, 6:33:00 PM https://news.ycombinator.com/news news.ycombinator.com###hnmain > tbody > tr:nth-of-type(4) > td The first line is just a comment informing you when and where you added it. It takes two mouse presses to disable the blocker for the current domain, so if something seems off it's easy to check.