I just noticed that in the documentation for smart.button is says:

“To initialize a button element the user has to include the following files to the head of the page:

smart.element.js – the base class

What does it mean that I need to include the base class?  If I have <my-element> and inside that I want to use <smart-button>…  Does <my-element> need to extend smart.elements.js?    That can’t be right…  Do I just need to reference it from my index.html?  I will try that.