<!DOCTYPE html>
<head><meta charset="utf-8"></head>
<body>
	<canvas id="canvas" width="200" height="200"></canvas>
    <script>
	let canvas = document.getElementById('canvas');
	let ctx = canvas.getContext('2d');
    for (let i=0; i<100; i+=50) {
        let arr = new Uint8ClampedArray(Array(40000).fill(200));
	    createImageBitmap(new ImageData(arr, 100)).then(img => {
		    ctx.drawImage(img, i, i);
	    });
    }
	</script>
</body>
