Option A: "standard way" => Class (in Angular example, use this snippet inside AfterViewInit lifecycle hook):

medium-wc-article--output-option-a.js

// OPTION A: "standard way" => Class
// In Angular example, use this snippet inside AfterViewInit lifecycle hook:
class MyAngularComponent implements AfterViewInit {

  ngAfterViewInit() {
    // Standard-way
    document.querySelector('#clickCounter')
      .addEventListener('counter-clicked', this.myCallbackFunction);
  }

}