The Canopy theme has a sidebar style cart drawer as well as a standard cart page. If you use the cart drawer, it has three settings for when it can show (located in Theme Settings > Cart): Open when cart icon is clicked, Open when a product is added to cart, Always visible (on larger screens).
The cart drawer is designed to give your customers a quick way to review the products they’ve added to their cart and it’s also a great place for you to include extra sales information. Add your choice of promoted products and a promotion image with overlay text. These advertisements are visible before your customers have added any items to the cart.
Once your customers have started add items to the cart, the promoted items are neatly tucked away in an accordion with your choice of heading text. As the cart fills up with products, the promoted items and promotion images will be pushed down below the items the cart – so the user can see the most products at any one time.
For cart drawers with lots of items, you can enable a setting to make your checkout buttons stick when the cart scrolls: