gerry3

import Component from '@glimmer/component';

export default class extends Component {
  activeIndex = 0;
  constructor(owner, args) {
    super(owner, args); // what is owner?
    // connections is provided here and is the same as @connections in the hbs file
    const connections = args.connections
    connections[this.activeIndex].active = true;
    

gerry3

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
	isActive: false,
  notActive: Ember.computed.not('isActive'),
  
  actions: {
    handleClick() {