Jquery Peer Dependency
It's required to use jQuery as a peer dependency in order for this library to hook into the special "page" events that the Shopify's checkout script emits.
You can choose to npm i jquery and then import it in your app.
Or, you can manually set the jquery instance this library uses through the options:
const csm = new CheckoutStepManager({ jQuery: window.$ });
Browser Script usage
This library emits a umd bundle that can be used if you want to include this library via a script tag.
This library is then exposed as window.CheckoutStepManager.