Google I/O 2019 SEO Key Takeaways

1. Googlebot now uses the latest version of Chrome as its rendering engine (WRS) and will be continuously updated with the latest version, the new evergreen Googlebot. Besides that, Google decided not to update Googlebot’s user-agent yet because they didn’t want to disrupt or break any websites, so they will let everyone know at a later date when that is planned for.
   With this latest update to the WRS, modern JavaScript is no longer a blocker for SEO, allowing sites to make the most of JavaScript features, without the need for as many polyfills as before. In fact, compared to the previous version, Googlebot is now able to support over 1,000 new features. Testing tools including Google Search Console and Google’s Mobile-Friendly Test will also be updated soon to reflect this, with the importance still being placed on user experience.
   It is important to remember that despite this update, the render queue will still be in place due to Google crawling, indexing, and rendering pages separately. While is delay still exists, it is important for websites to have a fallback, to ensure both Googlebot and users are still served useful content.
   In this case, Server Side Rendering (SSR) can be used to improve both the user experience and SEO of a site, with SSR and Hydration also being recommended, particularly for Web Apps, due to its ability to provide a dynamic nature even if the initial content is in HTML. Pre-rendering should also be considered, in particular for sites where the content doesn’t change often, for example landing pages and blogs. Read more on this
2. Big changes are coming to image search with the addition of the high-resolution image opt-in program, swipe up to navigate and 3D models in search. Also, Google recommends using lazy-loading with IntersectionObserver – which now works by default in the new version of Chrome.
3. A new speed report is being introduced to Google Search Console and webmasters can sign up for access to the beta version. The new Speed Report available in Search Console will feature field metrics based on the Chrome User Experience Report data. From this report, you will be able to see an aggregated view of your site’s key speed metrics, with the added ability to drill down into specific issues. From here you will be able to find examples of pages needing improvements, implement the fixes, and then monitoring these through the Chrome Developer Tools. Additionally, new Page Grouping will help site owners figure out where they are best placed to focus their resources when planning speed fixes.
   New updates to Lighthouse (v. 5.0) include a new UI (it will also be in the PageSpeed Insights and Chrome Canary and they’ve even added a Dark Mode option too), Lighthouse Stackpack, Lighthouse Wallets, and Lighthouse Plugins (these will allow you to track and measure KPIs that are specific to your site). 
4. The rollout of mobile-first indexing started last year and now more than 50% of sites are being crawled and rendered primarily using Googlebot smartphone. The team is striving for mobile-first indexing to be rolled out to all sites. Mobile-first indexing requires content, structured data, images, and metadata to be equivalent across desktop and mobile.
5. Some of the new types of structured data being introduced by Google include:

   (a) How-to markup for step by step tutorials to assist with real-world tasks;

   (b) Question and Answers markup provides support for people who have questions about a particular product or service;

   (c) FAQ content markup is similar to Q&A markup but for pages that have multiple questions on them.

6. Progressive Web Apps (PWAs) aren’t just for mobile anymore, they make it possible to deliver high-quality, capable apps on Windows, Mac, Linux, and Chrome OS. PWAs are websites with a few extra pieces. They bring app-like behavior to websites and break them out of the browser, giving users the best of both worlds. All major browsers now support PWA installation, including iOS. As of August 2019, Chrome will include the PWA install prompt in its Omnibox, which is their most prominent UI space.
7. SameSite Cookies will be rolled out over the next couple of months, which will introduce changes to how cookies work in Chrome to support transparency and control.
8. Puppeteer is now available for Firefox, while currently an experimental project, it already supports 90% of Puppeteer APIs Puppeteer can be used to automate testing, monitor performance, and diagnose issues.

Source: DeepCrawl TL&DR