Some background: I've started my professional career as a full stack developer back in late 1999, before the term was popular (perhaps even before it was coined?).
I've worked a lot with HTML4, CSS3 and Javascript, but some time around 2009-2010 (I think) I got pulled away from Web dev and got into desktop applications - so while I do have the basic knowledge of how things work, I have no experience whatsoever with current frontend frameworks and technologies (Didn't even had the chance to learn JQuery, when it was the shiny new thing).

So, if I want to land a job as a fullstack developer, what should I learn?