Incorrect (manual DOM manipulation in component):

// app/components/chart.gjs
import Component from '@glimmer/component';

class Chart extends Component {
  chartInstance = null;

  constructor() {
    super(...arguments);
    // Can't access element here - element doesn't exist yet!
  }

  willDestroy() {
    super.willDestroy();
    this.chartInstance?.destroy();
  }

  <template>
    <canvas id="chart-canvas"></canvas>
    {{! Manual setup is error-prone and not reusable }}
  </template>
}