Incorrect (no cleanup):

// app/components/live-clock.gjs
import Component from '@glimmer/component';
import { tracked } from '@glimmer/tracking';

class LiveClock extends Component {
  @tracked time = new Date();

  constructor() {
    super(...arguments);

    // Memory leak: interval never cleared
    setInterval(() => {
      this.time = new Date();
    }, 1000);
  }

  <template>
    <div>{{this.time}}</div>
  </template>
}