<model-viewer> is an open-source web component developed by Google and maintained through GitHub. <model-viewer> aims at putting 3D content on the web easily with a few lines of HTML code. This was first introduced with Chrome 72 in July 2019 and enables users to view 3D in the browser and mobile devices.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Next.js is a React framework for developing single page Javascript applications.
Unpkg is a content delivery network for everything on npm.