With the release of Chrome 88, you can now see Core Web Vitals data in the developer tools performance recording section. The lane currently displays Web Vitals information such as First Contentful Paint (FCP), Largest Contentful Paint (LCP) and Layout Shift (LS). In short, now there is a new lane of data for Core Web Vitals in this performance recording section.
Within Chrome 88's developer tools, under the performance recordings, you now have an option to display Google Web Vitals information. After recording your load performance, enable the Web Vitals checkbox in the Performance panel to view the new Web Vitals lane. This information lane currently displays Web Vitals information such as First Contentful Paint (FCP), Largest Contentful Paint (LCP) and Layout Shift (LS).
Here is a screen shot showing this in action:
Glenn Gabe said on Twitter that this is a "great addition."
Just make sure to update Chrome to 88, enable developer tools and check it out. It can help you debug these core web vital metrics in real time and in a super granular way.
A bit of a note on this in terms of HTTP content:
Generally, yes, but I'd be careful to make general assumptions about the network behavior of Googlebot based on Chrome, because rendering interfaces the network via our crawler
— Martin Splitt (@g33konaut) January 21, 2021
Right now, I don't know. I haven't tested this behavior yet.
— Martin Splitt (@g33konaut) January 21, 2021
It should be fine because Googlebot can access the HTML code but here is what it might render as:
Here is a screenshot of what it looks like. I hope that helps. pic.twitter.com/lT6uzROwmJ
— Glenn Gabe (@glenngabe) January 21, 2021
Forum discussion at Twitter.