This seems to be because you are accessing the DOM of the element from the constructor which is a no no. Here's a simple repro: https://stackblitz.com/edit/lit

This seems to be because you are accessing the DOM of the element from the constructor which is a no no. Here's a simple repro: https://stackblitz.com/edit/lit-element-react-attributes-location?file=my-element.js https://stackblitz.com/edit/lit-element-react-attributes-loc...