Rated 5 out of 5 stars
Perfect addon! I but I really with the interface was more use-friendly :) Even the basic stuff like changing the name of a blocking set... does it have to be at the bottom of the options page? does it have to look like it doesn't do anything, until you close the window and open it again?
Really small improvements, like changing the tab name while you change the name field, or hiding "Select when to block these sites" when no time periods or limit is specified, would make me feel like I'm working with a proper program, not an '80s terminal ;)
"Download the list now" near the "load from url" field would be also helpful.