Fetch getting previous data

Retired Boards Appdev Store Design
2

this.updateQuantity may still be resolving, when your attempt to fetch goes out so you are getting back the current data, just not the updated data.

Instead of onchange try using the PUB/SUB system in dawn subscribing the code to PUB_SUB_EVENTS.cartUpdate that happens after the updateQuantity function get it’s response

https://github.com/Shopify/dawn/blob/main/assets/cart.js#L170

for the subscribing pattern see https://github.com/Shopify/dawn/blob/main/assets/cart.js#L31C1-L36C8

Though to be sure you’d want to step through it the browsers devtools debugger , and observe the network calls.