Source: modules/quickedit/js/views/EntityDecorationView.es6.js

/**
 * @file
 * A Backbone view that decorates the in-place editable entity.
 */

(function (Drupal, $, Backbone) {
  Drupal.quickedit.EntityDecorationView = Backbone.View.extend(
    /** @lends Drupal.quickedit.EntityDecorationView# */ {
      /**
       * Associated with the DOM root node of an editable entity.
       *
       * @constructs
       *
       * @augments Backbone.View
       */
      initialize() {
        this.listenTo(this.model, 'change', this.render);
      },

      /**
       * {@inheritdoc}
       */
      render() {
        this.$el.toggleClass(
          'quickedit-entity-active',
          this.model.get('isActive'),
        );
      },

      /**
       * {@inheritdoc}
       */
      remove() {
        this.setElement(null);
        Backbone.View.prototype.remove.call(this);
      },
    },
  );
})(Drupal, jQuery, Backbone);