Read and inwardly digest the Structure and Interpretation of Computer Programs.
After that, whatever is next on the treadmill is just some new syntactic sugar on top of the fundamentals taught in that book, which you can pick up with a minimum of time and effort.
Occasionally there is something truly new, but those are few and far between.
Also, if you are seriously worried about your earning potential, read this and learn to really apply it, before picking up another Javascript framework:
After that, whatever is next on the treadmill is just some new syntactic sugar on top of the fundamentals taught in that book, which you can pick up with a minimum of time and effort.
Occasionally there is something truly new, but those are few and far between.
Also, if you are seriously worried about your earning potential, read this and learn to really apply it, before picking up another Javascript framework:
https://www.kalzumeus.com/2012/01/23/salary-negotiation/