cdnjs is a free distributed JS library delivery service.
Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
Popper is a positioning engine, its purpose is to calculate the position of an element to make it possible to position it near a given reference element.
ShareThis provides free engagement and growth tools (e.g., share buttons, follow buttons, and reaction buttons) for site owners.
Tippy.js is the complete tooltip, popover, dropdown, and menu solution for the web, powered by Popper.
Unpkg is a content delivery network for everything on npm.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.