That you can't tackle React before you've learned JavaScvript is an... universally accepted truth. But how much of it more precisely? How much JavaScript do you need to know before learning React? Is a reasonable grasp of the fundamentals enough or should you be able to... write your components from scratch? Is “having a clue” about the JavaScript syntax more than enough for jumping into a JavaScript library like React? Or it is necessary to dive way deeper into JS? To learn all about the DOM, to gain a good grasp of the object-oriented and functional programming concepts and so on?