[Question] Demo: Shepherd is not defined

I'm not a power user of js, for the least. But in the the "demo", Shepherd module is imported in a script tag:
index.html

<link rel="stylesheet" href="shepherd.js/dist/css/shepherd.css"/>
<script type="module" src="shepherd.js/dist/shepherd.mjs"></script>
<script src="demoScript.js"></script>

When imported like this, there is an error in the demo script, Shepherd is not defined.

For the example to work, i had to do differently:
index.html

<link rel="stylesheet" href="shepherd.js/dist/css/shepherd.css"/>
<script type="module" src="demoScript.js"></script>

demoScript.js

import Shepherd from "shepherd.js/dist/shepherd.mjs"

const tour = new Shepherd.Tour({
		defaultStepOptions: {
			cancelIcon: {
				enabled: true
			},
			classes: 'class-1 class-2',
			scrollTo: { behavior: 'smooth', block: 'center' }
		}
	});
//........

Question are, what did I miss, and how it is supposed to work with this import:
<script type="module" src="shepherd.js/dist/shepherd.mjs"></script> ?
I think a jsfiddle would be much more didactic than the current demo page.

Start with the script tags in index.html and the Shepherd usage in demoScript.js. Reproduce the demo with the module script as shown, then compare it with the working import in demoScript.js. Done means the demo loads without “Shepherd is not defined” and the intended import usage is clear.