<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<script>
function draw() {
	var c = document.getElementById('cc');
	var g = c.getContext('2d');
	g.fillStyle = 'red';
	g.fillRect(0, 0, 200, 200);
	g.font = '24px arial, sans-serif';
	g.fillStyle = '#fff';
	g.fillText('_\u00AD_', 10, 30);	// soft hyphen
	g.fillText('_\u200B_', 10, 60);	// ZWSP
	g.fillText('_\u200C_', 10, 90);	// ZWNJ
	g.fillText('_\u200D_', 10, 120);// ZWJ
}
</script>
</head>
<body onload='draw()'>
<canvas id='cc' width='200' height='200'></canvas>
</body>
</html>