Preconnect

Preconnect is a resource hint (``) that tells the browser to establish an early connection to a third-party domain. It performs the necessary DNS lookup, TCP handshake, and TLS negotiation in the background before a resource from that domain is actually requested. This "warms up" the connection, saving significant time later and improving the load speed of assets hosted on other domains, such as fonts, analytics scripts, or images from a CDN.