Sample code using screen to ID elements in the DOM instead of container or component with React Testing Library

rtl-screen-example.js

import React from 'react';
import { screen } from '@testing-library/dom';
import { render } from '@testing-library/react';
import { act } from 'react-dom/test-utils';
import App from './App';

describe('Product Browser App', () => {
  it('renders a welcome message', () => {
    act(() => {
      render(<App />);
    });
    screen.findByText('Hello world');
  });
});