Chrome APIsadvanced
Declarative Shadow DOM for server-rendered web components
<user-card>
<template shadowrootmode="open">
<style>
:host { display: block; border: 1px solid #ddd; border-radius: 8px; padding: 1rem; }
.name { font-weight: 600; margin: 0; }A <template shadowrootmode> is parsed straight into a real shadow root by the HTML parser — a web component's shadow tree, fully rendered before any JS runs.