An Adobe Commerce developer needs to improve the time of first render of the pages.

CSS critical path is a feature that improves the time of first render of the pages by inlining the CSS rules that are required to render the above-the-fold content of the page. This reduces the number of requests and bytes that need to be downloaded before the page is rendered. CSS critical path can be enabled in the Admin Panel by navigating to Stores > Configuration > Advanced > Developer > CSS Settings and setting Enable CSS Critical Path to Yes. References: Adobe Commerce Developer Documentation, Adobe Inc.