<html>
<head>
    <meta charset="utf-8"/>
</head>
<body>
    <custom-span text="בדיקה"></custom-span>
</body>
<script>
	class CustomSpan extends HTMLElement {
		constructor() {
			super();

			var shadow = this.attachShadow({ mode: 'open' });

			const span = document.createElement('span');
			span.innerText = this.getAttribute('text');

			shadow.appendChild(span);
		}
	}

    window.customElements.define('custom-span', CustomSpan);
</script>
</html>