How do I configure ESLint in VS Code for JS module script

I am using VS Code to work on a web page (using Leaflet). In my index.html I run the JS with:

<script type="module" src="js/main.js"></script>

I am using an ESLint plugin with VS Code and I want it to use strict JS rules for the linting, but though I have a “use strict”; at the top of main.js, it is only showing problems for non-strict issues.

I have an eslint.config.js file in the root of my project which looks like this:

import globals from "globals";
import pluginJs from "@eslint/js";

export default [
  {languageOptions: { globals: globals.browser }},
  pluginJs.configs.recommended,
];

What do I need to change to get ESLint to get it to respond to the “use strict”; command and what to do to make it the default so it’s not needed?

Thanks