Checkout Button Not Working

If your checkout button isn't working in the cart or mini-cart, it's likely due to the authentication-popup block being removed from the header content.

How the Checkout Button Works

Clicking the checkout button dispatches a toggle-authentication event. This event is processed by the authentication-popup block, which is declared in Magento_Customer/layout/default.xml and uses the Magento_Customer/templates/account/authentication-popup.phtml template. This template is crucial as it triggers a login form (if guest checkout is disabled) before redirecting to the cart.

<block class="Magento\Customer\Block\Account\Customer" name="authentication-popup"
       as="authentication-popup"
       template="Magento_Customer::account/authentication-popup.phtml"/>

This block is rendered within the parent template Magento_Theme/templates/html/header.phtml.

How to Check for a Missing authentication-popup

To verify if the authentication-popup block is missing, compare your theme's Magento_Theme/templates/html/header.phtml template with the original at:

vendor/hyva-themes/magento2-default-theme/Magento_Theme/templates/html/header.phtml

Your theme's template is likely missing this crucial line:

<?= $block->getChildHtml('authentication-popup'); ?>