I'm trying to load a sample LWC using the Light DOM (Beta) https://developer.salesforce.com/docs/component-library/documentation/en/lwc/lwc.create_light_dom

I've stripped it down to essentially their example and I still get the following error on running it on the local server:

Invalid directive "$lwc:render-mode" on element <template>.

My component:

<template lwc:render-mode="light">

    <p>Hello World</p>

</template>

JS:

import { LightningElement } from 'lwc';
    export default class YourekaForm extends LightningElement {
    static renderMode = 'light';

}

API version of the component is set to 57.0

I'm trying to load a sample LWC using the Light DOM (Beta) https://developer.salesforce.com/docs/component-library/documentation/en/lwc/lwc.create_light_dom

I've stripped it down to essentially their example and I still get the following error on running it on the local server:

Invalid directive "$lwc:render-mode" on element <template>.

My component:

<template lwc:render-mode="light">

    <p>Hello World</p>

</template>

JS:

import { LightningElement } from 'lwc';
    export default class TestForm extends LightningElement {
    static renderMode = 'light';

}

API version of the component is set to 57.0