With PWAs, you get native-like interactions, push notifications, and home-screen installation. But it’s only part of the picture. In addition, distribution is much easier with standard web-like linkability, shareability – and no-app-store distribution.
We’ve asked experts from the Elephate SEO agency about their findings and recommendations regarding PWA SEO techniques.
After conducting a series of experiments with the modern JS frameworks vs Google, the findings they presented are really interesting:
1. The fate of Chrome 41
Google parses and renders JS but with heavy limitations – it uses a headless browser based on Chrome 41 (2015’) … If you’re using modern Ecma Script specifications (as most devs currently are) your JS probably should use a lot of shims/fallbacks to provide the same code/links structure to the Googlebot. The worst part is – it’s hard to say which elements will be successfully interpreted and indexed by Google, and which will not.
Unfortunately for PWA app developers, in Chrome 41, interfaces like IndexedDB and WebSQL are disabled. The interfaces are most commonly used for providing your users with offline support.
2. Googlebot is not a browser
The World Wide Web is huge though, so Google optimizes its crawlers for performance. This is why Googlebot sometimes doesn’t visit all the pages the webmasters want.
Most importantly, Google’s algorithms try to detect if a resource is necessary from a rendering point of view. If not, it probably won’t be fetched by Googlebot.
Elephate’s experiments show that Google crawler does not wait longer than 5 seconds for any resource to be downloaded/rendered. Moreover, it could “optimize” your app behavior by not respecting (still pretty common) setTimeout() calls, etc.
Here the Google Indexer just omitted the script and rendered the rest of the page. Source: Elephate blog.
3. Googlebot doesn’t click anything
You should make sure whether or not a menu is apparent in the DOM before clicking on any menu items. If you rely on the onClick event, it can stop the browser from indexing your website structure.
4. Feel the flow
Source: Google I/O ’18
SEO techniques in PWAs
Vue Storefront is a standalone Progressive Web App storefront for your eCommerce, able to connect with any eCommerce backend (eg. Pimcore, Prestashop or Shopware) through the API. It’s made using the Vue.js framework – and yes it’s SPA (Single Page Application), and yes it works well with Google and other crawlers. You can find more info on our Github.
Web development tools and techniques are changing – much faster than search engine capabilities to handle all the new features. Google is still using a rendering engine – dating back to 2015 – to render most modern web-applications.
There is a solution. You can separate the content served for the crawler (rendered server-side) from the super-modern CSR (client-side-rendered) version for your users. You can do that. Legally. No consequences 😉