As expected, probably sooner than expected, Google has released a version one of their lazy loading guide for SEO. Martin Splitt from Google shared the news on Twitter saying "wanna get a glimpse on the first version of the lazy-loading SEO docs we've been brewing?"
The first version of the document is pretty short, it can be found here. It covers some of the early tips to making sure web pages that deploy lazy loaded content can also find that content in the Google search index.
Google's advice here includes:
- Load content when it's visible in the viewport: To ensure that Googlebot sees all content on your page, make sure that your lazy loading implementation loads all relevant content whenever it is visible in the viewport by using the IntersectionObserver API and a polyfill.
- Support paginated loading for infinite scroll: To support paginated loading, provide a unique link to each section that users can share and load directly. We recommend using the History API to update the URL when the content is loaded dynamically.
- Test: After you set up your implementation, you should make sure it works correctly. One way you do this is by using a Puppeteer script to locally test your implementation. Puppeteer is a Node.js library for controlling headless Chrome.
I am sure Google will continue to add more tips to this document but the concept of what Google expects should all be there by now.
Forum discussion at Twitter.