I was trying to add a "Go To Cart" button below the default "Add To Cart" button. I was able to inject another element with jquery like this:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
$(function() {
$("<a class='btn btn--border theme-btn--primary-inverse' href='/cart/'>Go to Cart</a>").insertAfter(".sqs-add-to-cart-button-wrapper");
});
</script>
But of course it doesn't get all the button styling. So I tried to add div parents to match other buttons on the site that look like this: