Slider feature from Clone isn't working, but works on clone

I was really impressed with the slider from this link:
https://showcasesearch.webflow.io/projects/https-webflow-com-website-multi-step-form-rfsn-1495911-39ce0

but when I copied the project, the slider doesn’t show up.
it just looks like this:

it only shows up when i publish it on the example site.
But then when I publish on my own site, the slider doesn’t appear at all.

could I get any help understanding how this slider is made?