Well, it is external JS, you need to include it in your banner file directly or in the package. It also is based in Intersection Observer and has the Polyfill in the source. I saw one could update the dependencies after all this time. Seem like Scrollama was updated meanwhile. I made a bundle from this called ScrollKit. You can also use Hype Action Events and add the polyfill there if you need to support older Browsers, I also just put some scrolling samples out that only work with on scroll, as well. Either way, using an Intersection Observer is more modern than doing some plain old scroll math.