Preconnect allows the browser to set up early connections before an HTTP request, eliminating round-trip latency and saving time for users.
A few examples of things you might want to utilize this for is to include your CDN URL or Google Fonts or any essential domain name for tracking script.
<link rel="preconnect" href="https://cdn.domain.com">
<link rel="preconnect" href="https://fonts.googleapis.com">
Preconnect is supported by most modern browsers, with some of the exceptions are Internet Explorer, Safari, IOS Safari, and Opera Mini.
You can easily implement preconnect by clicking on the “Advanced” tab in the Perform WordPress plugin and start adding domains, one per line.
Format: scheme://domain.tld (one per line)
Here are some of the additional resources for you to know more in-depth about preconnect and how it can help your WordPress site to skyrocket sales and conversions: