It used to be possible to create bookmarklets in Firefox that accepted parameters.
For example, you could create a bookmarklet to open superuser.com and search for a term. You could then assign the keyword super to launch the bookmarklet. Then, if you entered super firefox into Firefox's address bar, it would perform a search on superuser.com for the term firefox.
In current Firefox versions (61-63), I can no longer find a way to do this. Is it still possible?