Working with JS
Much like CSS, for JS to be loaded, the script needs to be referenced by a library, and then the library needs to be loaded by the theme. The JS can be placed in any directory but is typically placed in the themename/js directory.
Drupal behaviors
Drupal behaviors is the term for the JavaScript API that allows JS to process elements that are injected via AJAX.
It usually runs multiple times when a page is loaded. It’ll run first and pass in the document as context. The subsequent times it loads it will then pass in the AJAX element as context:
((Drupal) => {
Drupal.behaviors.myBehavior = {
attach(context) {
context.querySelector('.my-element')?.addClass('is-processed');
},
};
})(Drupal); In the preceding example, we create a behavior called myBehavior. We add this to the Drupal.behaviors array that Drupal runs whenever...