The old curriculum actually only had 2 parts, front end and back end. Once you completed both of those then you also got the full stack. The new curriculum is much more detailed, with more topics and is up to date, so dont worry about the old one
Its good to know at least one front end library…if you have strong foundational skills in JS and know React, for example, an employer will feel confident you can pick up any other js front end library. I see more and more front end job listings requiring RESTful API knowledge, and also testing. Thats basically the entire course.
The only one that I would say isnt absolutely necessary is the Data Viz, but even then, Im seeing D3.js and other data viz knowleldge listed as a nice to have / bonus / would be nice if you know this in job listings as well.
So yeah, basically…everything on FCC for Front End, for Back End, take a really deep dive into Data Structures and algorithms, as well as Node and DB’s… I consider Full Stack to include DevOps, but its a pretty loose term that can mean whatever your future employer wants it to mean.