I last worked as a web developer about two years ago, before going on a hiatus due to burnout. I worked with Cold Fusion, jQuery, and what was then the latest in HTML5, CSS, and JavaScript. There wasn't much acceptance of newer libraries and technologies due to the structure of the department.It seems that the world has changed quite a lot since 2019--nothing insurmountable, though quite varied in what technologies might now make up a stack.What wold you suggest that I learn, as someone who wants to bring their skill up to what the market seeks? A fellow suggested that I start by learning React and how to work with APIs and API development.If you will, what do you believe that a person MUST know in 2021 to be effective and attractive in the market?I'm willing to tackle anything.