Bug: ESlint not detecting Safari limited support of custom components

In CanIUse I found that Safari browsers have only limited support for the customized built-in-elements.
https://caniuse.com/custom-elementsv1

I have Eslint setup with compatibility checking in order to catch such problems.
However, it passes without errors which does not seem like correct behaviour.

My config:
```js
import pluginJs from "@eslint/js";
import compat from "eslint-plugin-compat";
import globals from "globals";

export default [
{
files: ["**/*.mjs"],
languageOptions: { sourceType: "module" },
},
{
files: ["**/*.js"],
languageOptions: { sourceType: "commonjs" },
},
{
files: ["functions/**/*.js"], // backend code
languageOptions: {
sourceType: "commonjs",
globals: {
...globals.node, // Include node globals like 'process'
}
},
},
{
files: ["tests/**/*.js"], // Jest tests
languageOptions: {
sourceType: "commonjs",
globals: {
...globals.browser, // Include browser globals like 'document' arising from puppeteer
...globals.jest, // Include Jest globals like 'test', 'expect'
}
},
},
{
files: ["public/**/*.{js,mjs}"], // Browser facing code
languageOptions: {
sourceType: "commonjs" ,
globals: {
...globals.browser, // Include browser globals like 'document'
}
},
settings: {
browsers: [
"> 1%",
"last 3 versions",
"not dead",
"defaults",
"not op_mini all"
]
},
plugins: {
compat: compat // Compatibility testing in browser facing code
},
rules: {
...compat.configs["flat/recommended"].rules,
}
},
pluginJs.configs.recommended
];
```

Sample code that should give errors:
```js
class FooterComponent extends HTMLElement {
/**
* Constructs a new instance of the Footer component.
*
* Is added as follows:
*
* [text]
*
*
* @class FooterComponent
* @extends {HTMLElement}
* @constructor
*/
constructor() {
super()
}
}

customElements.define('footer-component', FooterComponent, {
extends: 'footer'
})
```