One addition in the latest versions of Appfinder was the custom actions. I never used it until after I started typing several times twitter which didn't work (a habit from the web browser url bar).
The custom actions can be useful for anything, and it's really quick to run it.
Examples of custom actions:
twitter: xdg-open https://twitter.com/
us: setxkbmap us
It can be very handy, check the online documention for a quick setup. There are also online examples, don't mind to leave a comment or to fill the bugtracker if you have clever ideas, I can add them, I just did with the setxkbmap us example ;-)