Firefox announced that rel="preload" support is landing in Firefox 78. Preload allows you to kick start fetch requests before the browsers rendering engine kicks into place. This allows the browser to have these files sooner and will help to have those resources be rendering blocking. This was a popular way to allow CSS not to be rendering blocking. But, it was a situation that we had to polyfill for Firefox, and now that the support has landed natively in the browser, it is going to be something that we can start to reach for me more often.