What is the Dynamic Rendering recommendation?

How does Dynamic Rendering work?

The "Dynamic Rendering" recommendation supersedes the old Ajax crawling scheme specification.

Compared to this previous specification, it simplifies the way bots retrieve snapshots from your website in order to index pages. It also simplifies the changes you need to apply on your website to do so. For example, unlike the previous specification, you don't need to add a special tag in the HTML page content or to add the _escaped_fragment_= query parameter to get snapshots. Instead, bots are simply identified by their user-agent in order to transfer their requests to SEO4Ajax.

You can find more detailed information about this recommendation in the official documentation from Google.