Before talking about the new Audit feature, let’s take a look at how Google indexes page content, which is hidden in JS scripts.

JavaScript rendering is the creation of an HTML mask of a page that takes into account the changes made by JavaScript.

Previously, search engine crawlers only crawled and indexed content that was stored in static HTML source. Today, many sites use JavaScript frameworks and libraries (Angular, React, Vue.js, and Polymer).

Sites made in JS do not display the content of the page by the server. The content is loaded using JS in the user’s browser. For example, here is the Serpstat main page that uses React scripts. What the user sees:

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