Export Snapshot Link

Canvas content is converted into a data URL and assigned to a download link so the drawing can be saved.

Program

toDataURL serializes the current canvas bitmap. A link with download can offer that image as a file.

export_snapshot_link.html

<canvas id="chart" width="320" height="180"></canvas><a id="save" download="chart.png">Save chart</a>
<script>
  const chart = document.querySelector("#chart");
  const save = document.querySelector("#save");
  const ctx = chart.getContext("2d");
  ctx.fillStyle = "#0f766e";
  ctx.fillRect(24, 36, 180, 72);
  const url = chart.toDataURL("image/png");
  save.href = url;
</script>

toDataURL toDataURL converts the canvas bitmap into an encoded image URL.

download The download attribute suggests saving a link target as a file.