ah i understand..
so first things first, you know you can create easily regex supported aliases in FARR that will let you do this.
for example, check out the built in aliases for imdb, just type "imdb slackers" to open imdb and search for that movie.
the farr aliases are going to be faster than searching your ff bookmarks and so would usually be preferred.
however, that's not to say that it wouldnt be useful to add this support to farrfox, and it might be a nice excercise, so i will put it on my todo list.
still, i think you should consider just using normal farr aliases to do this because of the speed advantage.