<html xmlns="
http://www.w3.org/1999/xhtml">
<head>
<script type="application/x-javascript">
customElements.define("custom-element", class extends HTMLElement {
constructor() {
super();
const template = document.getElementById("template");
const shadowRoot = this.attachShadow({mode: "open"})
.appendChild(template.content.cloneNode(true));
}
});
function runTest() {
var div = document.getElementById("testDiv");
// First we have to make sure that we've looked up the primary frame for
// the textnode. Appending a space should do the trick.
div.firstChild.data += " ";
// Now flush our reflow
document.body.offsetWidth;
var node = document.createElementNS("
http://www.w3.org/1999/xhtml",
"span");
div.appendChild(node);
node.appendChild(document.createTextNode("This text should appear"));
}
</script>
</head>
<body onload="runTest()">
<template id="template"><span><slot/></span></template>
<custom-element id="testDiv" style="width: 0; display: block;">This is text in a div</custom-
element>
</body>
</html>
