<script src="include.js"></script>
<my-custom-element></my-custom-element>
<script>
    test(() => {
        class MyCustomElement extends HTMLElement {
            constructor() {
                super();
                const shadow = this.attachShadow({ mode: 'open' });
                const style = document.createElement('style');
                shadow.appendChild(style);
                println(`shadow.styleSheets.length=${shadow.styleSheets.length}`);
                println(`document.styleSheets.length=${document.styleSheets.length}`);
            }
        }

        customElements.define('my-custom-element', MyCustomElement);
    });
</script>