As others have mentioned and I believe you were referring to, Firefox does let you create bookmarks with keywords to accomplish the same thing. Funnily enough,

As others have mentioned and I believe you were referring to, Firefox does let you create bookmarks with keywords to accomplish the same thing. Funnily enough, I've often seen Firefox users unaware that they can do the same with custom search keywords in Chrome, so the problem runs both ways. As someone who uses these features in both Firefox and Chrome, I do think it would be nice if Firefox copied how Chrome automatically adds these search actions, and perhaps a bit of the UI polish too (like how Chrome's omnibox will recognize you're performing a keyword search and adapt accordingly). It doesn't make much of a difference for existing power users, but it could help new users discover and use the feature.