ReferenceError: Header is not defined using standalone, pure-JS mode

[partofthething]

Describe the bug
I copied the demo code from the Readme into a html file and opened it. It gives an error on the Console:

ReferenceError: Header is not defined

Even if I comment the line that's coming from out (from options), then there are no errors but nothing shows up on the page. Just a blank page.

To Reproduce
Steps to reproduce the behavior:

1. Copy readme's HTML to a html file
2. Open it in web browser
3. See error and/or blank screen

Expected behavior
I'd expect a demo similar to what's shown in the screenshots to appear.

Screenshots
Just blank screen

Desktop (please complete the following information):

• OS: Windows 7 64-bit
• Browser Firefox 66.0.2, Chrome 73.0.3683.103

[neuronetio]

I've updated readme, try it now

[partofthething]

Totally works. Thanks!