Question:

Is it possible to update multiple cart items?

Carson: 2 weeks ago

To be more specific I would like to add an "update cart" button so that the visitor can adjust the quantity of multiple cart items without having to click on "update" for each cart item.

Answer:
Charlie: 2 weeks ago

Not at the moment, you can submit a feature request for the feature here: https://github.com/craftcms/commerce/issues