If you're a Shopify Plus customer, you can now display the Zipchat Bubble directly on your checkout page.
To enable it, follow these steps:
Shopify Admin > Online Store > Edit theme > Switch to "Checkout and Customer accounts" > Add the Zipchat Checkout script.
If you're not a Shopify Plus customer, you can still show the Zipchat Bubble on the thank you page by following the same steps.