Issue:

Ordered items/products not showing in Magento Order Confirmation email after upgrade to Magento 2.4.4

Expected Result:

Order confirmation email should contain the list of ordered items for both registered and guest orders

Actual Result:

Ordered products are missing from order confirmation email Magento 2.4.4

Fix:

Login to Magento admin > Marketing > Email Templates > Open the order email template and find:

{{layout handle="sales_email_order_items" order=$order area="frontend"}}

and replace with:

{{layout handle="sales_email_order_items" order_id=$order_id area="frontend"}}

.. clear cache and this should resolve this issue.