Wouldn't loading css asynchronously cause FOUC?

[littlee]

Wouldn't loading css asynchronously cause FOUC?

[scottjehl]

I'm confused, will this code below cause FOUC

That's correct. You would want to use async CSS loading for low-priority stylesheets that aren't critical to the initial page rendering. The CSS file for google fonts is one example where people have used this. Or, the styles for a chat or reviews widget that are shown after user input could be a candidate for async loading. Additionally, some sites inline their most important CSS and async-load the rest, broken apart by which styles are used in the first visible sections of a page.