This

The readonly this binding applies to every element (and component) and allows you to obtain a reference to rendered elements. For example, we can get a reference to a <canvas> element:

  1. <canvas
  2.     bind:this={canvas}
  3.     width={256}
  4.     height={256}
  5. ></canvas>

Note that the value of canvas will be undefined until the component has mounted, so we put the logic inside the onMount lifecycle function.