Squarespace Checkout Customization JavaScript

Question

I'm a first time Squarespace user trying to inject JavaScript into my website so that I can customize the checkout button to redirect customers to a quote form instead of the regular checkout. I'm having trouble getting it to actually work. When I click on the button there are no errors in the console. The result is still a direction to the default checkout page after it redirects to the correct form for half of a second. The button seems to be dynamic. At first, I wasn't able to correctly target the button, but now the console prints the correct actions to recognize the button being clicked.

    document.addEventListener("DOMContentLoaded", function() {
        function checkout(event) {
            event.preventDefault(); // Prevent default behavior
            console.log('Checkout button clicked.'); // Log that the button was clicked
            window.location.href = '/quoteform'; // Redirect to checkout form
        }
    
        // Function to initialize checkout button and event listener
        function initializeCheckoutButton() {
            const checkoutButton = document.querySelector('.WPMtsTeKIf6hjb69ukR9.cart-checkout button, .d_v7cGDEhQylt5v3Moan.sqs-editable-button.sqs-button-element--primary.cart-checkout-button');
    
            if (checkoutButton) {
                checkoutButton.addEventListener('click', checkout);
                console.log('Checkout button found and event listener attached.');
            } else {
                console.error('Checkout button not found.');
            }
    
            // Debugging output
            console.log('Checkout button:', checkoutButton);
        }
    
        // Delay initialization until all elements are fully loaded
        window.addEventListener('load', function() {
            // Initialize checkout button after load
            initializeCheckoutButton();
    
            // MutationObserver to detect when the checkout button is added to the DOM
            const observer = new MutationObserver(function(mutationsList, observer) {
                for (let mutation of mutationsList) {
                    if (mutation.type === 'childList' && mutation.addedNodes.length > 0) {
                        // Check if any of the added nodes match the checkout button selector
                        const checkoutButton = mutation.target.querySelector('.WPMtsTeKIf6hjb69ukR9.cart-checkout button, .d_v7cGDEhQylt5v3Moan.sqs-editable-button.sqs-button-element--primary.cart-checkout-button');
                        if (checkoutButton) {
                            checkoutButton.addEventListener('click', checkout);
                            console.log('Checkout button found and event listener attached (dynamic).');
                        }
                    }
                }
            });
    
            // Start observing changes 
            observer.observe(document.body, { childList: true, subtree: true });
        });
    });

I've used the following code. Is there a reason why this is forcing a redirect to the default page or have any other script suggestions to prevent this?