It was just over a year ago that Dan Leibson open sourced aggregate Lighthouse performance testing in Google Data Studio (yet another resource in the SEO industry inspired by Hamlet Batista). I’d like to share with you some observations I’ve made over the past year of running Lighthouse testing on our clients’ sites and how I think Google’s render service operates. 

I’ve noticed some interesting similarities between how successfully Google renders a page and the measurement thresholds in Core Web Vitals that define good scores. In this post I’ll share a few methods to investigate Google’s rendering and how I feel that relates to LCP. 

There are plenty of other resources by excellent SEOs if you need a general overview of Core Web Vitals. Today I’ll be talking almost entirely about LCP.

Google’s Core Web Vitals – As Reflections Of Googlebot’s Tolerances

Here’s a quote from Google before I really dive into the realm of “SEO Theory”. These two quotes are from a Google Webmasters support thread, where Cheney Tsai compiles a few FAQs regarding Core Web Vitals minimum thresholds for acceptable performance; this part specifically about PWAs/SPAs.

Q: If my site is a Progressive Web App, does it meet the recommended thresholds?

A: Not necessarily since it would still depend on how the Progressive Web App is implemented and how real users are experiencing the page. Core Web Vitals are complementary to…