How to add the value of the additional modx field to the js file?

Question

JavaScript

How to take value from extra field and put it into variable in javascript file?
let a = Вопрос;

Answer 1

Assume a field: well, the code
let foo = document.getElementById('foo').value

Answer 2

Owl Carousel 2 try it!

Answer 3

Slick slider

$('.slider').slick({
    slidesToShow: 1,
    slidesToScroll: 1,
    dots: true
});

Style yourself