We've looked into ways that would enable us to import search engines that have already been added to Firefox, but Mozilla's Search API does not allow us to have access to the search query strings. That information stays hidden from developers, so we can't import the built-in search engines into Context Search. We have sought help from Mozilla to allow us to import search query Urls, but they have refused in a very authoritarian way. Thanks for your understanding and rating. It's very encouraging!