Cart API - Cart Icon dont update with new quantity

Hello, i have followed the Cart API reference to successfully set a post request that adds items to the cart: https://shopify.dev/docs/api/ajax/reference/cart

However, cart icon (#1) is not being updated with the new quantity?. I have to refresh the page to see cart items being added, I’m using the default theme?

Is there any shortcuts to emit/dispatch new items being added to the cart so these will update automatically on the page? also, the popup (#2) that comes when you add cart items with the normal button, does not pop up either?

I can add “sections” to the request like so: (saw this in the original request from the normal add to cart button)

fetch(window.Shopify.routes.root + `cart/add.js`, {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json'
    },
    body: JSON.stringify({
        'sections': 'cart-notification-product,cart-notification-button,cart-icon-bubble',
        'items': [{
            'id': window.ShopifyAnalytics.meta.selectedVariantId,
            'quantity': 2
        }]
    })
})
    .then(response => {
        return response.json();
    })
    .catch((error) => {
        console.error('Error:', error);
    });

That will return some HTML, from the response:

"sections": {
"cart-notification-product": "

\n 
### CC Was Here\n <dl></dl>
\n 

",
"cart-notification-button": "Se indkøbskurv (5)\n
",
"cart-icon-bubble": "\n \n\n\n\nIndkøbskurv
55 varer\n 

"
}

Are you supposed to just inject this into the dom? lol…