Google Fonts now fully supports variable fonts in the v2 API update. We’ll| Google for Developers
The preconnect HTML hint allows the application to tell the browser which sockets it will need ahead of initiating the actual requests; preconnect eliminates DNS, TCP, and TLS roundtrips from the request's critical path.| www.igvita.com
What is that preload? What does it do? And how can it help you? Preload gives developers the ability to define custom loading logic without suffering the performance penalty that script-based resource loaders incur. In human terms, it’s a way to tell a browser to start fetching a certain resource, because you as authors know that the browser is going to need that particular resource pretty soon.| Smashing Magazine