What is CLS by Chrome version
CLS by Chrome version shows Cumulative Layout Shift (CLS) values segmented by the version of Google Chrome your users were on. This lens helps you spot layout instability introduced by specific browser versions.
Only Chrome versions that generated real user traffic during the selected period are shown. This includes both mobile and desktop Chrome.
New Chrome versions often introduce changes to rendering behavior, font handling, and layout calculations — all of which can impact CLS. Older versions may lack support for performance APIs or preload strategies, leading to more layout shifts.
Healthy CLS by Chrome version sample
If the latest Chrome versions (with the most traffic) are green, you're in good shape. Some instability on older versions is acceptable as long as they represent a small fraction of users.
Unhealthy CLS by Chrome version sample
If the most recent version of Chrome is showing bad CLS, that’s a sign something on your site isn’t working well with the latest rendering logic. This can happen due to:
A Chrome engine update affecting layout behavior
Late-loading fonts or elements without dimension hints
A frontend change that wasn’t tested on newer versions
Visual regressions in components like banners or sticky headers
If older Chrome versions are performing poorly but still have meaningful traffic, check whether your site relies on modern layout techniques not supported in those versions.
Resolving unhealthy CLS by Chrome version
Go-to action plan to resolve an unhealthy CLS by Chrome version:
Ask Uxi to analyze your CLS by Chrome version values and suggest improvements
Use Filters to isolate the version with the worst layout shifts.
Simulate CLS of the suspected lens to see if fixing it will resolve the CLS by Chrome version. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by Chrome version values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
Try it yourself
Discover how your website performs with real user data.